THE 



iiiiiR, iiimie 



T 



iiraiisii. 



A PEACTICAL TEEATISE, 



ILLUSTRATED WITH FOUR HUNDRED ENGRAVINGS. 



BY 



ROBERT GRIMSHAW. 



^A^' 



C^ 





NEW YORK : 
HOWARD LOCKWOOD, 74 DUANE STREE']-. 



1883. 



Cn 






9 



Entered, according to Act of Congress, in the year 1882, by 

HOWARD LOCKWOOD, 

In the Office of the Librarian. of Congress at Washington, D. C. 




^<^ 



LOCKWOOD PRESS. 74 DUANE STREE"^ NEW YORK 



JS 



PREFACE. 

J7 

sN preparing this book for a large class of practical men, only slightly 
\ represented in technical literature, the author has aimed to give it 



i 

t a wider range than any work of the kind yet presented. 

The material has been gathered from various sources. Many 
mills have been visited ; interviews and extended correspondence have 
been held with practical and successful millers, millwrights and millfur- 
nishers. The author has adapted and freely quoted from standard works, 
and from his own and other articles in the principal milling journals. 

Much of the information given answers questions asked by those 
interested. 

A large part of the work has been verified by competent specialists, 
whom the author heartily thanks. 

Some of the subjects are mooted questions among the most skilled 
in the art ; and in many such instances the claims of both sides are 
stated. 

This book is intended not only for occasional reference, but for daily 
use. Many of the calculations and tests have been made specially for it. 

It is not offered as infallible ; but should be convenient and useful, 
and may serve as a basis for something better. 

Philadelphia, May i, 1882. 



PUBLISHER'S NOTICE, 






|HE Publisher, in offering this work to the milling public, wants to 



'^i^' sa)' that, recognizing the desirability of a practical and useful 
handbook in the arts of milling, millwrighting and millfurnishing, 
he engaged the services of an unbiased author, already well known in 
technical literature, with instructions to spare neither care nor expense 
in producing a correct and useful work. The task — which was a long 
one — is finished. The amount of matter as here presented is about three 
times greater than that in the largest prior work on the subject in the 
English language, and the illustrations are numerous and interesting. 
The style is clear and concise, and the work proves to be so compre- 
hensive, that it has been thought advisable to print a much larger edition 
than was at first intended. The price has been made low so as to meet 
the demands of a large number of readers. 



TABLE OF CONTENTS. 



Chapter I.— MILL CONSTRUCTION. 

Page. 
Site— Plans— Cost of Excavation— Foundations — Frost — Walls (Stone)— Bricks— Mortar— Batter— 
Partitions— Chimneys— Beams — Floors — Doors and Windows — Sheathing— Plastering — 
Roofs— Leaders — Skylights— Ventilation — Lightning Rods, etc.— Paints — Fire-Proof Con- 
struction — Fires and their Causes — Artesian Wells— Tanks — Pumps — Hose — Hydraulic 
Ram— Chemical Extinguisher — Fixed Water Pipes — Steam Pipes — Heating— Lighting — 
Estimates, ............. 9, 

Chapter II.— MILL PLANS. 

Roller and Burr MUls — New Process Burr Mill — Three-Run Mill— Two-Run Low Grinding Mill — 
Niagara Falls Mill— Burned Yaeger Mill— Deseronto Mill— Five-Run Eurr Mill— Two-Run 
Burr Mill— Mill Office— Seven-Run Mill— Oliver Evans' Mill, ... .41 

Chapter III.— MILLING DIAGRAMS. 
Milling Diagrams, ............. 71 

Chapter IV.— POWER. 

Waste of Power — Relative Cost of Steam and Water Power — Steam vs. Water — Power per Barrel 

of Flour. ............ 75 

Chapter V.— WATER-WHEELS WITH HORIZONTAL AXES. 

Kinds of Wheels— Undershot— Breast— Overshot — Vertical vs. Turbine Wheels— The Largest 

Water-Wheels— Screw Flood Wheels, . . . .77 

Chapter VI.— TURBINES. 

Theory— Vertical Wheels vs. Turbines— Useful Effect- The Victor AVheel— Ordering Wheels- 
High Falls— Steps— Clogging— Variations of Power— Water-Wheel Governors, . . 80 

Chapter VII.— SETTING WHEELS, Etc. 

Setting Wheels— Areas- of Races and Flumes— Building Flumes— Position of Flumes— Decked 
Penstock— Details of Raised Penstock— Low Falls— Open Penstock— Wooden Flume for 
Turbines under High Falls— Sizes of Gripes— Draft Tube— Racks— Flood Gates, . 99 

Chapter VIII.— MEASURING WATER-POWER. 

Falls— Theoretic Velocity and Discharge— Rules for Measurement by Weirs— Measurement by 

Floats— Stream Power— Work of Water-Wheels by Night and Day, . . . .107 

Chapter IX.— BOILERS. 

Combustion— Fuels— Waste of Fuel— Material for Boilers— Effects of Heating— Testing Plate- 
Boiler Shapes— Laterally Fired Horizontal Boilers— Internal Firing— Tubular— Water 
Tubes— Elephant— Proportions— Draft Area of Tubes— Steam Room— Weakening EfCects 
of Common Steam Domes— Flues and Tubes— Grate Bars— Setting— Smoke Consumers- 
Chimneys- Cowls-Steam Pipe- Dry Pipe — Safety Valves — Fusible Plugs- Pressure 
Gauges-Glass Water Gauge— Draft Regulator— Feed Pipe— Feed Pump— Injector-Steam 
Traps— Blow-Off Valve— Blowers— Heating and Filtering Feed-Water— Corrosion, Ex- 
ternal, Internal— Grooving—Incrustation — Character of Scale — Scale Preventatives— 
Management, ......••• .114 



CONTEXTS. 

Chapter X.— THE STEAM ENGINE. 

Page. 

Steam — Mechanical Effect — Expansion — Throttling and Wire-Drawing — Back Pressure — 
Economy of High-Pressures— Condenser— Compression— Speed — Superheated Steam — 
Steam Jacket— Lagging — Governor — Gardner's Governor — Foundation— Steam Cylin- 
ders—Fly-Wheel — Stroke— Steam Chest— Area of Steam Ports— Piston Head- Piston 
Rod — Slides— Cross-Head— Connecting Rod— Crank Pin— Crank— Piston-Head Packing— 
Piston-Rod Packing — Care of Steam Engine— Pounding— Cylinder Lubrication— Indicator 
Diagrams and Expert Tests — Wheelock Engine — Computation of Horse-Power— Power 
and " Duty "—Cost of Putting in Steam Power— Cost of Fuel per Barrel of Flour, . . 157 

Chapter XI.— TRANSMISSION— SHAFTING. 

Shafting— Turned Shafting— Cold Rolled— Hot Finished— Hollow Shafts— Hangers-Bearings — 

Torsion — Couplings — Friction Clutch — To Line Up Shafting— Keys, . . . .188 

Chapter XII.— TRANSMISSION BY BELTING. 

Belts; vs. Gears — Elements in Belt Transmission — Rubber Belts— Cotton— Rawhide— Leather — 
Duration— Requisites for Successful Belt Transmission— Tension — Sag— Tightening Pul- 
leys—Lacing—Putting on Belts— Testing Strength and Grip— Laying Out— Carrying Power 
aroTmd a Corner by a Belt— Shifter, ......... 199 

• Chapter XIII.— TRANSMISSION BY CHAINS. 
Detachable Link Chain, ............ 216 

Chapter XIV.— TRANSMISSION BY GEARING. 

Gearing— Loss of Power through Gears— Laying out Gear Teeth— Mortise Gearing — Laying out 

the Teeth of Mortise Wheels— Gear Wheels, ........ 280 

Chapter XV.— TRANSMISSION— PULLEYS. 

Pulleys— Stepped Pulleys— Split Pulleys— Loose Pulleys— Idle Pulleys— Tractive Force— Lagging 

—Bevel and Mitre Friction Pulleys, ......... 229 

Chapter XVL— ROPE TRANSMISSION. 

Location of Power— Transmission of Power by Wire Ropes — Distance of Transmission— Driving 
Ropes — Sheaves for Wire Rope — Deflection of Ropes— Long Transmissions— Rope Con- 
necting Rods, ............ 837 

Chapter XVII.— FRICTION AND LUBRICATION. 

Friction — Function of Lubricant — Hot Bearings — Lubricants — Compounded Oils — Evaporation- 
Spontaneous- Combustion — Purity — Action of Oils on Metals — Bearing Metals — Propor- 
tions of Bearings, ........... 241 

Chapter XVIIL— BACKLASH AND SIDE PULL. 
Backlash— Coil Spring— Side Pull, . . . . • . . . . - .251 

Chapter XIX.— GRAIN CLEANING. 

Cleaning — Ending — Screens— Grading and Separation— Hungarian System of Cleaning— Cockle 
— Cockle SeparatiOB— Oat Separation— Grader and Dustless Separator— Smutter and 
Separator — Wheat Brush. .......... 354 

Chapter XX.— WHEAT DRYING AND HEATING. 

Drying Wheat— Heating WTieats— Generators for Wheat Heaters in Water Mills— Thermometer 

Attachment for Wheat Heaters, ........ 279 



COXTEXTS. 

Chapter XXL— GRANULATION AND GRINDLNG. 

Page. 
General Classification of Granulating and Grinding Devices — Disc Milling — Material of Discs- 
Burr Millstones— Oscillating Upper-Runner Horizontal Mill— Oscillating Under-Runner 
Horizontal Mill— Rigid Runner Horizontal MiUs—Under-Runners— Vertical Mills— Iron 
Discs— Iron Cones— Methods of Driving Rolls— Cylindrical Rollers— Single Roller Work- 
ing against a Curved Face— Materials of Rollers— Surface of Rollers— Grooved ChUled 
Iron Rolls— Smoothed Chilled Iron Rolls— Smooth Porcelain Biscuit Rolls, . . .283 

CirAPTER XXIL— THE BURR-STONE. 

Various Stones used for Grinding — Burr-stone Proper — La-Fert6-sous-Jouarre— Ordinary Mill- 
stones, ............. 288 

Chapter XXIIL— MOUNTING THE BURRS. 

The Millstone— Building Up the Burrs— Size and Weight of Stones— Hurst Frames — Hoppers and 
Hopper Frames— Pinion Jack— Size of Pulleys— The Spindle— Different Forms of Cock- 
heads— Setting the Bed— Tramming and Bridging— Iron Jackstick with Level — To Make 
a Tram— Bush— Tram-Pot—Stiff vs. Oscillating Drive— The Balanced Bail— Ordering a 
Bail — Drivers — The Dane Driver — Equilibrium— Balancing the Runner — Standing Balance 
— Running Balance— Centrifugal Force— Radius of Gyration— Putting in Running Bal- 
ance—Point of Suspension — The Damsel Feeders — Automatic Stone Lift — Iron Burr 
Crane- Oiling MiU Spindles— Fitting a New Back— Cost of Building Up, . . .295 

Chapter XXIV.— VARIOUS MILLSTONE DRESSES. 

The Dress— Choice of Dress— Path of Material— Elements of Dress— Eye— Bosom— Face— Pro- 
portion of Land and Furrows— Duties of Furrows— Number of Quarters— Number of 
Furrows— Outline of Furrows— Circle Furrow— HoUandish Circle Dress — Improved Circle 
Dress— Logarithmic Spiral Dress— Angle of Furrow Crossing— Laying Out Circle Fur- 
rows—Direction of Furrows— Draft-Depth of Furrows— Furrow Section— Smoothness 
of Lands and Furrows Old Quarter Dress— The Hughes Dress — Compromise Dress- 
Pennsylvania and New Jersey Dress— Old Style Equalizing Dress— New Style Equalizing 
Dress- Combination Dress— Dickson Dress— Southern Dress— Jones Dress — Bowman 
Dress— Amdt's Dress— Ward's Millstone Formula— Dressing for Regrinding— Other 
Dresses (for Old and New Process, for Middlings, for Corn, for Wheat, etc.) 319 

Chapter XXV.— DRESSING THE BURRS. 

First Dress— Picks- Tempering Mill Picks and Chisels— Position in Dressing— Paint Staff— Proof 
Staff— Staffing— Direction of Furrows— Draft Square— Furrow Strip— Redressing and 
Cracking- Cleaning Millstones — Mending Burr Faces— Pick Burr Dresser — Diamond 
Dressing— Benton Dresser— Hand Tools. ........ 344 

Chapter XXVL— OPERATION OF THE BURRS, 

Operation of Grinding- Diameter of Burrs — Table of Rim Speeds— Speed of Grinding— Dress and 

Quality of Stone -Trouble in Grinding— Quality of Burr Flour, .... 35? 

Chapter XXVIL— COOLING THE CHOP. 
Millstone Ventilation— High-Pressure Aspiration, ........ 361 

Chapter XXVIII. —ATTRITION BY AIR-BLAST. 

Attrition by Air-Blast, ............ 366 

Ch.^pter XXIX.— IRON DISC MILLS. 
Iron Disc Mills — Raymond Brothers' Mill — Jonathan Mills' Disc Machines, . . 367 

Chapter XX.X.— DETAILS OF DIFFERENT TYPES OF BURR MILLS. 

Classificaiion of Mills— Usual Type of Mill.— Munson's Geared Under-Runner Mill— Munson's 

Portable Mill Spindle— Plantation Mills, ........ 378 

Chapter XXXI. —SYSTEMS AND PROCESSES. 

Progress of Modern Milling— Hungarian Roller System— Why Hungarian System is Compli- 
cated-Details of 150Barrel System— A 450-Barrel Roller Mill, . , .379 



CONTENTS. 

Chapter XXXII.— DETAILS OF ROLLERS AND FRAMES. 

Page. 

Roller Milling— Varieties of Roller Machines— Number of Rolls, Single and Three High— Jones'/ 
Single Roll Frame— Roll Pairs— Method of Driving— Length of Rolls— Diameter of Rolls- 
Surface of Rolls— Materials of Rolls— Soft-Irou Rolls— Forms of Corrugations— Stevens' 
Patents— Number of Corrugations— Twist of Corrugations— Feed and Pressure— Axial 
Pressure— Differential Speed— Speed Ratios— Capacity 9f Round Rib Rolls— Yield from 
Roller Milling— Amount of Break Flour— Color— Strength of Roller Flour— Power Re- 
quired by Rolls— Labor Required with Rolls— Coolness with Roll Work— Rolls on Soft 
Wheats— Break Rolls for Soft Wheats— Break Rolls for Mixed Wheats— Rolls on Mid- 
dlings—Bran Cleaning by Rolls— Gray's Roller Frame, . . . . .386 

Chapter XXXIIL— MIDDLINGS MACHINES. 

Middlings Machines— Middlings Milling by Burrs— Middlings Purifiers— Principle of the Purifier- 
Grading Middlings— Kinds of Middlings— Dusting Middlings— Keeping the Cloths Clean- 
Collecting and Grading Flour Dust — The G. T. Smith Purifier— Middlings Returns- 
Clothing — Number and Size of Purifiers— General Remarks on Purifiers- Grinding Un- 
purified Middlings — Bran Cleaning, ......... 406 

Chapter XXXIV.— BOLTING. 

Bolting— Methods Employed— Bolting Cloths— Wire Cloths— Silk and Wire Bolting Cloths Com- 
pared—Mending Cloths — Cleaning Cloths— Putting on the Cloth — Sliding of the Chop- 
Speed of the Reels — Capacity of Reels — Care of the Bolts — Keeping the Cloth Clean— 
Reels— Bolting Chests— Speck Box— Improved Bolting Chest— Screw Bolt Feeder— Rules 
for Clothing— To Get out Middlings— Clothing for Single Reel— Three Reels— Six Reel 
Chest — Scalping- Dusting Reel— Custom Work— Altering Reels— Reels in the Hungarian 
System— Wire-Clothed Reels— The Centrifugal Machine— Wheat Meal Purification- Re- 
bolting — Bolting for Custom Mills — Hints, ........ 427 

Chapter XXXV.— ELEVATING, SPOUTING AND CONVEYING. 

Elevating— Link-Belt Elevators — Elevator Boot — Elevator Buckets— Air-blast Elevator— Storage 
Elevators— Hoppers and Sinks— Spouting— Endless-Chain Conveyors — Hollow-Shaft Con- 
veyor — Pitch of Screw Conveyors— Discharge — Flexible Conveyor— Hoisting, . . 453 

Chapter XXXVL— WEIGHING, TESTING, PACKING, BRANDING 

AND STORING. 

Scales — Grain Meter— Inspection of Flour and Meal — Packing— Economic Flour Packer — Tallies 

— AdjustableTally— Electric Tally— Brands, etc.— Storage, . . . . 470 

Chapter XXXVIL— CHANGING AND ALTERING MILLS. 
Changing Dress, etc., for New Process— Altering Blills, ....... 482 

Chapter XXXVIII.— MILLWRIGHTING. 

Tools — How to Treat and Use a File— Marking OlT- Timber Joints— Halving Together — Open 
Mortise and Tenon Joints— Regular Mortise and Tenon Joint — Blind Mortise and Tenon 
Joint — Dowel Joint — Various Methods of Setting the Bevels of a Hopper — Building an 
Overshot Wheel, . . . . . ... . . . .487 

Chapter XXXIX. — COMPOSITION AND STRUCTURE OF THE 

WHEAT BERRY. 
Composition and Structure of the Wheat Berry. ........ 508 

Chapter XL.— GRAIN DESTROYERS. 
Vegetable Organisms— Weevils — Rats, ......... 518 

Chapter XLL— MISCELLANEOUS. 

Helps to the Miller— Dut3-— Ordering Machinery— Choice of Stone — Straightening Shafts— Cost 
and Depreciation of Machinery— Cost of Manufacture— Qualities of Wheat— Cost of 
Wheat Transportation — Prices of Wheat — Calculations— Problems and Solutions, . . 521 



ALPHABETICAL SUBJECT INDEX 



TO TEXT AND ILLUSTRATIONS. 



[ Illustrations are marked with an asterisk *.] 



Look for each Subject under the most Important Word in it. 



s, 



ABSOLUTE Steam Pressure, 
Acid, Acetic, for Scaling Boiler 
Acid, Carbonic, 

" Impurities in Feed- Water, 

" Phosphoric, in Wheat, 

" Sulphuric, In Wheat, 
Action of Furrows, * 

" of Oils on Metals, . 

" of Smooth RoUs,* 
Actual Expansion Rates of Steam, 
Adamson Joint for BoOer Flues, 
Adhesion of Belts, .... 

Adjustable Tally 

Advantages of Belt Transmission, 

" of Wire Drawing, . 
A ir, Analysis of , . 
Air-Blast Elevator,* 
Air Current in Burrs, 

" Pressure of, . 

" Required for Combustion of Various 

Fuels, 115 

" Volume of, Unconsumed, . . . 114 

'■ Seasoned Lumber, .... 19 

" Weight of 114 

"Air Space'" Boiler and Pipe Covering,* . 146 

Albumen, . . 509 

Albvmiinoids in 'Wheat, 510 

Alignment of Shafting, ..'... 175 

'■ Improper, 177 

Allls & Co., Mill Plans, ... 42, 47, 54, 58 
Roller Frames,* . . 402, 403 404 



PAGE. 

1G3 
153 
114 
150 
511 
511 
3:i4 
248 
390 
159 
12G 
200 
478 
1'j9 
161 
114 
458, 159 
333, 361 
157 



Almond Oil, Action on Metals, 

Altering Mills, Cost of , . 

Altering Two-run Mill, , 

American Spring Wheat, Analj'sis, 

Amidon ( see Starch), 

Analysis of Various Materials (see Index 
for each material). 

" Anchor R" Blocks, 

Andemach Stone, 

Angle of l^'riction of Chop, . 

Angle of Furrow-crossing, . 31 

Animal Oil in Boilers, . 
" '"in Cylinders, 
" " upon Rubber Belts, . 

Aniseed for Joints, .... 



249 
482 
481 
511 
510 



288 
288 
330 
32S, 330, 331 
150 
175 
200 
520 

Anthracite Coal, 116, 125 

" " Air Required for Combus- 

tion of, . . . 115 

Anti-friction Metal, 193 

Anti-Incrustator for Boilers, . . . 153 
Arc of Contact of Belts, Influence of, 199, 202 

Arches, above J^Iume, 13 

" Brick, 30 

" Flat, 20 

" Terra-Cotta, for Floors, ... 20 

Area of Boiler Tubes, 123 

" of Burr Faces, 358 

" ofCliimneys, 137 

" of Flume 100 

" ofHead-Race 100 

" of Safety -Valve, Thurston's Rule, . 141 

" of Steam Ports, 169 

" ofTaU-Race 100 



PAGE. 

Arkell & Smiths' Paper Flour Sacks, . . 477 

AiTidt Dress, Under-Runner for Rye,* . 339 

" " Under-Runner for Wheat,* . 340 

Artesian Wells, 34 

Asbestos Cement Boiler Covering, . . 146 

" Lagging for Steam Engines, . . 165 

" Paclang 171 

Ash, Wood, 116 

" in Fuel, 116 

" in Wheat, 510 

" of Wheat, Horsford's Analysis, . . 511 

Ashes Causing Corrosion of Boilers, . 150 

" under Boilers, 153 

Asphaltic Coal, 116 

Atmospheric Pressure 161 

Attachments for Detachable Malleable 

IronLmkChams,* . . . 218,219 

Attic, 22 

Attrition Mill, 366 

Augers, . 487 

Automatic Engines, Care and Manage- 
ment of, 174 

" Stone Lift 316 

" Stop for Coil Spring, .... 252 

" Stop for Governor, . . . 166 

Available Heat, 114 

Average Total Steam Pressure, . . 159, 184 

Axe, 487 



BABBITT-METAL, . 
" for Bearings, 
Backing up Millstones, . 
Backlash, 

" Caused by Belt Elasticity, 

" from Gear Wheels, 

" Motion Indicator to Detect, 

" of Involute Gear Wheels, 
Back Pressure, 

" from Feed-Water Heaters, 
Back-Water, Trouble from, . 

Bad Gearing 

Bags' (See Sacks.) 

Bail and Driver, the Dane,* . 

BaU, Ordering, ... 

Balanced Bail, .... 

Balance Rynd, Laying Off and Cutting 

Holes in, 
Balance. Running, 

" Standing, 

" W^rong,* 
Balancing Burrs,* 

" at Various Speeds, 

" the Runner, . 
Balance Weight, Attaching a,' 
Balancing Device for Millstones * 
Baragwanath's Feed-Water Heater, 
Bariting Shafting, 
Bark in Turbines, . 
Barley, Screens for. 
Barrels, Hoops for, . 

" Packing in, 

" Paper, 

" TaUies for, . 



161, 162, 
75, 



202, 



30' 



the 

7, 



308, 
307, 



310, 



193 

249 
318 
251 
251 
251 
251 
228 
184 
149 
79 
177 

306 
304 
304 

301 
309 
308 
310 
311 
309 
307 
308 
.311 
148 
190 
96 
264 
476 
476 
476 
479 



INDEX. 



PAGE. 

476 

133 

131 

17 

18 



Barrels, Wood-Pulp, 

Barr's Table of Grate Areas, 

Bars, Grate, 

Batter of Walls, 

Beams, Hodgkinson, 

" Iron, 

" Lagging of . 

" Strength of, . 
Beator Macnines, . 
Beard of Wheat,* . 
Bearings, . 

" Brass, 

" Graphite for Hot, 

" Iron, 

" Length of, 

'■ Main, Running Hot, 

" Pressure on, . 

" Proportions of, 

•• Soft-Metal, . 

" Sulphur for Hot, 

" Wear of, . 

" Upright Iron Journals for, . 
Bearing Metal, Copper and Tin, . 

Bfichamp, 

Bed-stone,* 

Beech 

Behms and Brehmer Exhaust,* . 
. Belts, Adhesion of , . 

" Arc of Contact, Influence of, 

" Bending of 

" Robert Briggs on Tractive Force of 
Leather, 

'■ Broad, 

■' Buying Rubber, 

" Carrying Power Around a Comer 
by,* 

'■ Chemically Tanned, .... 

" Clamps for, Walden's Tension Regu- 
lating,* 202, 203 

" Cotton, 200 

" Crossed, 199 

" Cutting Holes in Floors for Straight 

Open,* 310 

" Double, . , SOI 

'■ Driving Power of Single Leather 201 

" Driving Side, 202 

" Dry Leather, 300 

" Duration of, 200 

" Effect of Animal Oil upon Rubber, 300 

" Elasticity of, Causing Backlash 351 

" for RoUer Frames, .... 389 

" for Wood-W^orking Machinery, . 202 

'• Friction of, . : . . . 200, 203 



19 
18 
283 
513 
193, 202 
249, 250 
244 
349 
250 
173 
250 
250 
250 
344 
245 
192 
249 
510 
375 
116, 117 
363, 364 
300 
203 
200 

333 

200 
200 

313 
200 



199, 



Glue for. 

Grain Side of Leather, 

Half Tmst,* . 

Heating of, . 

Horizontal, 

Horse-power of, . 

How to Put on, 

H. R. Towne upon Tractive Force of. 

Inclined, 

Influence of Contact Area, 

" " Position of, . 

'■ " Speed of, . 

" Tension of, 
and Width of. 
Lacing. . ' , 

Laying Out, 

Laying Out Holes for Quarter Turn, 

Leather, 

Link,* 

Long, for Conveyors, 

Loss of Driving Power, 

Material, Influence of, 

Moist, ... 

Narrow, . . 

New Leather, 

Oak Tanned, 

OUing, 

Open, 

Plan and Elevation of Quarter-twist, 

Quarter-tm-n, 

Quarter-twist, 

Rawhide, 

Rubber, . 

Sag of, . 

Screeching of. 

Seams of, 

Semi-Tanned, 



199, 



211, 212, 



305 
202 
313 
203 
202 
201 
206 
233 
199 
199 
.199 
199 
199 
199 
205 
209 
210 
200 
218 
219 
201 
199 
200 
201 
202 
300 
201 
199 
214 
309 
213, 214 
200 
200 
,^J02 
203 
206 
200 



300, 



Belt 



Belts, Shifter for 

" Single Leather. 

'• Slack 

" Slipping of . . 

■' Slipping of Rubber, 

" Speed of, . . . 

" Splicing, J. H Cooper, 

'■ Stiffness of Single Leather, 

" Strength of Single Leather, 

" Stretching, 

" Succeeding Gears, 

" Tensions of, .... 
Belt. Tests of E. F. Bradford i Co.'s, 
Belts, Te.sts of Driving Power, 

" Tests of Grip, 
Belt Tests, Leather, ... 

" Tests of New York Belting and Pack 
Co.'s., 

" Tests of Rubber, .... 
Belts, Strength of, . 

" Thick and Thin, 
Thickness of. 

Tightener for Richmond City Mill 
Works, 

" Tightener, Improved,* 

" Tightening, 
Belts, Tractive Force of Leather, 

" Transmission of, A. B. Couch on, 

" upon Flouring Machinery. 

" V. Gears, 

" Weight of Leather, 
Belting, Length of CoUs, 

" System for 450-bbl. Roller Mill, 

" System for 150-bbl. Roller Mill, 
Benduig of Belt, .... 

Bent I'urrows.* 

Bentou Diamond Burr Dresser,* . 

Best .Tournal Boxes for Shafting, 

Beveled Friction Pulleys. 

Bevels, Setting Hopper, 

Bevel Shell Wheels,' . 

Bilgram's Method of Laying out Gears, 

Birch, 

Biscuit Rolls 

Bituminous Coal, .... 

■' " Air Required for, 

Blacklead as Lubricant, 

" in Steam Cylinders, 

Black Mortar, 

Black Sea Wheat 

" " Analysis, . 

Black Weevil, . . 
Blast Machines, .... 
"Bleeding " of Boilers, . 
Blind Dowel Joint,* 

" " with Mitre,* . 

Blind, Single Mortise and Tenon,* 
Bhsters oii Boilers, .... 
Block Rubber, Hand,* . 
Blowers for Boilers, 
Blowing off Boilers, 
Blow-off Valve, .... 
Boarts for Bm-r Dressing, 
Boiler, Arrangement of, 

•■ and Pipe Covering with Air Space,* 

'■ Compound for, G W. Lord's, 

" Connections, .... 
Boiler-Covering, 

" " Asbestos, 

Chalmer's Spence, 
Hair Felt, 

'" •• Sectional Plaster, 

Boiler, Explosions of, . 

■' Foaming 

'• Front, \\-ith McGinniss Smoke 
sumer,* 

■■ Heads, Thickness of, 

■ • Plates, Burning of. 

Effect of Heating on. 
Mild Steel, 

" '■ Strength of, 

" " Testing of, 

" Proportion, 

■' Required to Heat Buildings, 

" Rignter, . . 

" Scale, 

" Setting, 

" HoUow Walls for, . 

" " Lime Mortar in, 

" " Proportions of, 



PAGE. 

215 
199, 301 

203 



203, 
200, 



203, 



303 
204 
201 
205 
201 
201 
204 
199 
203, 205, ;J44 
209 
20J 
207 
209 



2U7 
209 
207 
199, 300 
199 



202, 



200, 



230, 



116, 



203 
204 
177 
233 
199 
202 
199 
201 
536 
385 
384 
300 

324, 325 
355 
193 
235 
500 
224 
221 
116 
390 
135 
115 
245 
176 
17 
523 
511 
519 
283 
153 
499 
500 
497 
155 
356 
147 

152, 155 
145 
354 
264 
146 
153 
155 

134, 145 
146 
140 
146 
146 
138 
142 



Con 



119, 



137 
123 
127 
120 
119 
120 
121 
125 
38 
123 
125 
134 
134 
135 
137 





/A^DEX. 


iii 




PAGE. 




PAGE. 


Boiler Shapes, 

" Shells 


121 


Boilers, Molasses for Scaling, 


153 


121 


" Necks of, . . . 


125 


'• French, 


125 


" Oak Bark for Scaling, . 


153 


" Tubes, Arrangement of, 


123 


" Petroleum for Scaling, 


153 


" Tubes, Draft Area, 


127 


" Potatoes for Scaling, . 


153 


■' Tubes, Fastening, . . . . . 


130 


" Preventing Scale in, 


152 


'• Tubes, Lengths of, ... . 


123 


•' Priming, .... 


126 


" Tubular, 


122 


'■ Rectangular, . 


121 


'• Water, Condition of, . 


15i 


" Removing Scale in. 


153 


Boilers, . . 114, 119 1 


" Replacing, 


125 


" Animal Oil in, 


150 


" Scale, Character of. 


152 


'■ Anti-Incrustation for, .... 


153 


■' Scale in 


125 


■ Area of Tubes, 


123 


■' ScaUug, .... 


125 


'" Acetic Acid for Scaling, 


153 


'• Seamless Steam, . 


131 


" Bleeding of, 


152 


" Sectional Covers, . 


146 


" Blisters on, . . . 


155 


" Setting, .... 


122 


" Blowing off, . . ... 


155 


" Slippery Elm for Scaling, 


153 


" Blowing Down, .... 


152 


" Soda Ash for Scaling, . 


153 


" Bridge Walls for, .... 


135 


" Soft Deposits m, . 


l.i2 


" Cause and Remedy of Foaming, 


138 


" Soot Causing Corrosion of. 


150 


" Cane Juice Vinegar for Scaling, 


153 


" Smut in, . 


153 


" Carbonate of Lime in. 


152 


" Starch for Scaling, 


153 


" Carbonate of Lime in Feed, 


153 


" Staying of, . 


128 


'■ Carbonate of Magnesia in. 


153 


" Steel, ... 


119 


" Cast-Iron, 


119 


" Sulphate of Lime in, . 


152, 153 


" Catechu for Scaling, 


153 


" Sumach for Scaling, 


153 


'■ Chalk in, 


152 


" Sweeping, 


126 


■ Circulation of, ... . 


127 


•' Tamiic Acid for Scaling, 


153 


" Cleaning, .... 


127 


'■■ Tubes for. 


122 


" Common Salt in Feed-Water, . 


151 


" Tubulous, 


124 


•' Compound Tubular, 


1,24 


" Two-Story, . 


122 


" Cooling Down, .... 


52, 154 


" Vertical I'ire Tube, 


121 


" Copper, 


119 


" Washing out. 


152 


" Cornish, 


122 


" Water Tube. . 


124 


" Corrugated Flues, 


122 


" Wisconsin Water for, . 


150 


" Corrosion by Ashes, .... 


150 


" Wrought-Ii'on, 


119 


" Corrosion by Galvanic Action, . 


150 


Boiling Point of Water, . 


157 


" Corrosion by Sulphm-ous Coal, . 


150 


Bolt Feeder. Screw,* . 


435 


'• Corrosion by Soot and Ashes. . 


153 


Bolting Chests,* . . 


41, 433 


'■ Corrosion by Wood Fuel, . 


150 


Bolting Cloths, SUk (see special chap- 


'■ Corrosion of, . . . 


150 


ter,)* 


427, 428 


•■ Corrosion of 


125 


'■ Cloth, Wire*, F. G. Richardson's 


" Croton Water for, 


151 


Acme, .... 


429 


•' Cylinder Oils in. . . . . 


153 


Bolting for Spring Wheat, . 


487 


" Cylindrical .... 


121 


Bolts, Parting up of. 


361 


" Distillery Slops for Scaling, 


153 


Boot, Elevator, 


454, 4.55 


" Dry Pipes for, 


138 


Boring Steam Cylinders, 


168 


" Earth Oil for Scaling, . 


153 


Bosom, 


321, 343 


" Effect of Pure Water in, . 


150 


Basalt Burrs, ... 


288 


" Elephant, 


i;32 


Boussingault, Analyses of Whea 


t, 505 


'■ Expert Advice Concerning, 


153 


Bowling Hoop, 


126 


" External Corrosion of, 


150 


Bowman Dress,* 


339 


" Fairbairn, 


122 


Boxes, Plate, .... 


193 


" Filling Up 


155 


" Setting Driver, 


303 


" Fire Surface, 


127 


" Staffing, 


171 


•• Flues of, Adamson Joint for. 


126 


Box Journal, .... 


192 


" Foaming, 


125 


" Pivot. .... 


192 


" For Lime-Water Districts, . 


148 


" Self-Oihng Post Journal,* 


193 


" Foundations for Setting, . 


134 


Bracket for Conveyor Coupling, 


195 


" Foaming in, 


155 


Bradford, E. F., & Co , Belt Tests 


5, . 209 


" Foaming Caused by Sulphate of 




Brake for Fast-Running Macnine 


ry, . . 215 


Lime in, . . . . . 


153 


" Friction or Pony, 


177 


" Foaming in 


155 


Bran, .... 


512 


" Fruits for ScaUng, 


153 


" Danger from Fire by, . 


32 


" GaUoway, 


122 


" Dresser, Lawton & Amdt's 


426 


'■ Glass Gauges for, .... 
" Grate Surface 


155 


" Duster, Plans for. 


42 


123 


" Inspection of , 


475 


" Grooving of, 


126, 151 


" Rolls 


395, 482 


" Hanging of, . . . . 


137 


Brand, . . 


518 


" Heating Surface, .... 


123 


Brands and Stencils, D. D. Childs 


, . . 481 


" Hemlock Bark for Scaling . 


153 


Brass Bearings, 


249. 250 


" Horizontally and Vertically Fired, 


131 


Bread from Flour, Quantity of. 


525 


'■ Incrustation of, ... . 


151 


Breadth of Gear Teeth, 


226 


'■ Inclination of 


137 


Break, Reels fo'-,* . 


443 


" Internal Corrosion of, . 


150 


Breast Wheels, Loss of Water-Pc 


)werby, . 77 


" Internally Fired, ■ . 


122 


Brick for Arches, 


30 


" Iron in VVater, 


152 


" As a Fire-Proof Material, 


29 


" Joints of, 


126 


" Hollow Walls of, . 


29 


" Lugs for, .... 


135 


" Laying, per Day, Speed of 
Bricks, Number per Cubic Foot ( 


, . . 16 


" Lake Superior Water for, . 


150 


)f Wall, . 17 


" Lancashire, . . 


122 


" per Cubic Yard of Brick-w 
" Required for Walls, Numb( 


ork, . 17 


'• Leakage Caused by Con-osion, . 


150 


jr of, 16 


" Leaks of, . . . 


155 


" Strength of, . 


16 


" Life of, 


1.53 


" Test of 


16 


" Lifting Water in, . 


126 


" Walls of, ... 


15 


" Logwood for, .... 


153 


" Waste of, ... 


17 


" Low Water in 


154 


" Weight of. 


16 


" Management of, . 


153 


Bridge Walls for Boilers, 


125, 135 


" Marbie in 


l.i2 


Briggs, Robert, upon Tractive 


Force of 


'• Materials for, 


llfl 


Belts 


233 



IV 



INDEX. 



PAGE. 

Bronze Phosphor, 193 

Brown on Altering Mills, .... 483 
" on Method of Getting Running Bal- 
ance, 312 

Brush, Champion Wheat,* .... 277 

" Lubricant for 245 

" Ordinary,* 301 

Bucket, Elevatm\ 456 

" Shape of Water- Wheel, ... 77 

Buck Mountain Coal, 116 

Buckwheat, Screens for, .... 264 

" To Remove Wild, 267 

Burrs, Air Cm-rent in, 333 

" Balancing,* 311 

" Basalt, 288 

" Blocks for. Size of, . . . 288, 289 

" Building up,* .... 290, 295 

" Canary-colored, 288 

" Cement for Joints, .... 29 

" Cost of Building 308 

" Cost and Depreciation of, . . . 522 

■■ Circumference of, .... 358 

•' Crane Irons for,* .... 316, 317 

" Dark-colored, 2S8 

'■ Diameter of, 358 

" Drab, .288 

■' Driving Two Lines of, on One Shaft, 211 

Burr Dresser, Diamond,* .... 354 

Emery-Wheel, ... 356 

" Picks, 354 

" Dressing, 341 

" Braits or Cadbons for, . 354 

" Faces, Area of, 358 

Cement for 354 

Cracking 336 

" " Mending, 854 

" Rings in, 293 

" Flour, QuaUty of, 360 

" Mil], Building for, 44 

" Three-Run, 42 

" " Two-Run, 42 

" 450-bbl., 42 

" Fuel Requu-ed for Two-Run, . 42 

" " New Process, .... 42 

" Noye & Sons' Two-Run, . . 67 

" Eye of, 303 

" Expansion of, 359 

" for Com 388 

" for Dry Grain 288 

'■ for Oats 288 

Burrs, Gradual Reduction on, . . . 380 

" Granite, 288 

" Gumming of 257 

" How to Order, 40 

" Hughes' Rule for Draft in, . . . 333 

" Jumping of, caused by Light Feed, . 96 

" Lara 288 

" Lead-colored, 288 

'" Leveling, • 297 

' ' Method of Driving Two Lines of, from 

One Shaft,* 211 

" Ordering, 294 

" Plaster for Backs of , . . . 318 

" Poi-phyry, ' . 288 

" Quality of 288 

'■ Rim Speed of, 358 

" Rubbing 353 

" Sandstone, ' 288 

" Scrubbing 257 

Burr, Section of,* 303, 321 

Burrs, Speed of, for Middlings and for 

Wheat, ...... 482 

" Trachyte, 288 

" Washing, 353 

" Weighting, 317 

Burr Stones 284, 288 

" Cologne, ...... 285 

" Esopus, 285 

" French, German, Georgia Gray, 

Himgarian, Peninsular, . . . 285 
" Sardinian, Sarospataker Varie- 
gated, West Vu-ginia and White, . 288 
" New Stock, YeUow, various grades, . 289 

" Manufacturing, 288 

Building an Overshot Water-Wheel, . . 504 

" Height of, 10 

" for Burr Mill, 41 

" for RoUer Milling, . . , . 41 
" up the Burrs, . . . . 290, 295 

" Flumes, 100 



PAGE. 

Buildings, Boiler Required to Heat, . . 38 

" Proper Time to Erect, . . . 14 

" Proportions of, 10 

" Settling of, 10 

Bunt 518 

Bnming of Boiler Plates, . . . . 127 

Burning of Carbon, 114 

Burning Sawdust, ...... 132 

Bush 297 

Kuehne & Bryants 300 

Buying Rubber Belts, 200 

" Shafting, 190 

" Steam Engines, 185 

^lAKING Coal, 116, 117 

\J Calandria Granaria, .... 519 

Calandra Pryzo', . . . . . 519 

Callipering Shafting, 189 

Calculations, 526, 537 

Caldwell Conveyor,* 467 

California Wheat, 511, 523 

Carbo-hydrates, 510 

Camber, 19 

Cameron, Professor, 511 

Camphor for Weevils, 520 

Candles, 38 

" Danger from, 33 

Cane-Juice 'V^inegar for Scaling Boilers, . 153 

Cannel Coal, . 117 

Capacity of Hydraulic Ram, ... 36 

" of Stones, 322 

" of Tanks, 34 

Carbon, Burning of, 114 

Carbons for Burr Dressing 354 

Carbonate of Lime in Boilers, . . 152 

" ■ "in Boiler Feed-Water, 147, 153 

Carbonate of Magnesia in Boilers, 153 

Carbonic Acid, 114 

" Oxide 114 

Care of a Steam Engine, .... 173 

Careful Firing, Economy of , . . . 119 

Carrying Power around a Comer by a Belt, 212 

Cascade Mill Water-Wheel, .... 78 

Case for Proof-StaflE,* 349 

Casein 509 

Cast Gears, 220 

Cast-iron Boilers, 119 

" Disks 285 

" Engine Cranks, 170 

" PUlars, 14 

" Pulleys, 202 

" Radiators, 37 

" Steam Cylinders, 168 

Castor-OU, Action on Metals, . . . 249 

" for Leather Belt, ... 204 

" "as Lubricant, .... 245 

Catechu for Scaling BoUers, ... 153 

Causes of Fires, 31 

Ceilings, 30 

Cellar Walls, Mortar for, .... 17 

Cellulose in Wheat, . . . . 510 

Cement for Cold Weather Mason Work, . \'y 

" for Leather PuUey Covers, . . 235 

" for Joints of Burrs, .... 290 

" for Leather Belts, .... 205 

■ " for Burr Faces, 354 

Centre-Lift Tram-Pot,* 303 

Centrifugal Reels,* . . 445, 446, 447, 448 

Centre-Vent Turbines, 81 

Centrifugal Force, .... 307, 308, 309 

" " in Millstones. . . . 332 

" Governor, 165 

CereaUne, 507 

Chaff, to Take Out, 265 

Chalk-Line, 490 

Crossing of Fiurows,* . . . 328 to 332 

Croton Water for Boilers, .... 151 

Cro^vn of Pulley, Influence of, . . . 199 

" Roller Mill, Power Required, . . 76 

Crushing Strength of Mortar, ... 17 

Cubic Feet in Tanks, 34 

Curbs, 296 

" Cost and Depreciation of, . . 522 
Curved Dress, . . . . 324, 328, 329, 330 

" FiuTOws, 324 

Cushion in Steam Engine, . . . ' . 163 

Cut Gears, 220 

Cut-off of Slide-Valve Engine, ... 174 
" of Steam Engines, . 158, 158, 161, 161 



INDEX. 



Cutting Holes in Floors for Straight Open 

Belts,* 

Cylinder Lubricants, 

" Lubrication, 1 

" Oils as Lubricants, . . . 

" " in boilers, 

" Steam, Animal Oil in, . 

" Blacklead in, 

" Boring, 

" Cast-Iron, 

" Graphite in, 

" Horizontal ...... 

" Material for, 

" Mineral Oils in, 

" on Cups for, 

" Plumbago in, 

" Scale caused by Animal Oil in, . 

" Steel Bushes for Engine, 

" Vertical, 

" Work of Steam in, ... . 
Cylindrical Boilers, 

" RoUs, 

Chains, Attachments for Driving,*. 

" Transmission by, 

" D Tighteners for Detachable Link, . 

" Sprockets for Detachable Link, 

" Detachable Link, 

" Driving Elevators by, . . . . 

" Ewart Driving 

" Malleable Iron Driving, 

" Lubricating Sprockets, 
Chalk in Boilers and Feed-Water, 
Chalmers Spence Boiler Covering, 

■' •■ Flue Cleaner, . 
Chamber, Combustion, 

" Super-heating 

" Champion " Grader and Dustless Sepa- 
rator,* 

Changing Mills (see Altering), 
Character of Boiler Scales, .... 
Charcoal, Air Required for Burning, . 
Cheapness of Power, . . . . 

Cheat, to Remove, 

Check "Valve, 

ChemieaUy-Tanned Belts, ... 
Chemical Extinguisher, ... 

Cherry Coal 

Chests, Bolting, 

" Sts-reel, 

" Steam, 

Chicago River Water for Boiler Feeding, 

" Sawhide Manufacturing Co. 

Chilled Cast-iron RoUs 

Childs, S. D., Brands and Stencils, 

Chisels, 

Chimneys, 

" Area of, 

" Diameter of, 

Chloride of Lime for Rats, . 

Chlorine for Rats 

Choice of Dress, . . 



210 
148 
176 
245 
153 
148 
176 
168 
168 
176 
169 
168 
14S 
176 
176 
175 
168 
169 
184 
121 
286 
219 
216 
219 
219 
216 
217 
216 
216 
219 
, 152 
146 
154 
125 
139 

274 
482 
152 
115 

75 
256 
139 
200 

37 
117 
433 
440 
169 
150 
200 
390 
481 
48T 
18, 138 
137 



14, 



41 



of Stone 

(See also sub-heads). 

Chokes, 

Choking in the Eye, 

" Chordal '" upon Split Pulleys, 

Chop, Angle of Friction, 

" Distribution by Furrows, 

" Heating, 322, 

" Cups for, 

" Cooling the, 
Christy Brothers & Co., Power Required, 
Chute'Case, Outer, of Victor Wheel, 
Chutes of Turbines, 
Cigar Coat of Wheat Berry 
Circles, Areas, &c , . 
Circle Furrows, 

" ■' Laying Out, 

" Quarter Dress,* 

" Dress, Improved, . 
Circular Iron Proof Staff,* 
Circulation of Boilers, 
Circumference of Burrs, 
Clawson WTieat Starch,* 
Claviceps purjjurea 
Cleaning Boilers, 

" Flues, 

" Grain, 

" MiUstones. 

" Machinery, WTiere to Place 



325. 



324, 



137 

520 

520 

. . 319 

288—294, 521 



41 



177 

315 

230 

331 

331 

361 

311 

361 

76 

87 

81 

513 

526 

326 

3;32 

325 
327 
349 
127 
358 
516 
519 
127 
153 
253 
353 
254 



427, 428, 



441, 
439, 



451, 



441, 450, 



Cleaning Machinery of Simpson & GaiUt 
Manufacturing Company, 

" Machinery for 4o0-bbl. Mill, 

" Screens for, . 

" System for Hominy, 

" AMieat, Screens for, 

" Winter Wheat, 
Clearance in Steam Engines, 

" Lack of. Causing Leakage, 
Clearing Curve of Gear Wheels, 
Clogging 

'^ of Middlings, . 

" of Turbines, . 

" of Millstone's Eye, 
Cloth, Silk, Wire, Bolting, Xc, 

" BroT\-n's Riile, 

" for Custom Reels, . 448, 449, 450, 451 

" for Custom Mill, . 

" for Custom Work, 

" for Dusting Reel, . 

" Four Reels, 

" for Hard Sirring Wheat, 

" for Hungarian System, 

" for Merchant Work, 

" for Blichigan WTieat, . 

" for New Process, . 

" for One-Run, . 

" for Red Winter Wheat, 

" Rules for. 
Clothing Reels, Best Way to Cut Cloth, . 

" " for Scalpers (see xmder sub- 

heads), . . . 442 

" '■ for Seven-Run MUl, 

" '• for Single Reel, . 

" " Six-Reel Chest, 

" for Soft Wheat, . 

Three-Run MUl, . 441 

" " to Get Out Middlings, 

to Take Out Dirt, 
Two-RimMill, 
for 20-foot Reel, . 

" " for 24-foot Reel, . 

" " two Reels, .... 

Close Stones, Furrow Siulace for, 

I losure. Exhaust, 

Clutches, Finger,* 

" for Line Shafting,* . . . 195, 

" Friction 196, 

Coal 

" Air Required for Anthracite and Bi- 
tuminous, 

" Anthracite, 115, 

" Asphaltic, 

" Bituminous, 

" Buck Mountain, 

" Cannel 

" Caking, 115, 

" Cherry, 

" Consumption, . . 

" Consmnption of Boilers, 

" Dust, Danger from Fire by, 

" for300-bbl. MiU 

" Gas, 

" Harleigh Lehigh, 

" Hydrogenous 

" Long Flaming 

" per Barrel of Flour 

" Scranton, 

' ' Semi-Bituminous, 

" Shaley, 

Cocks, Gauge, 

Cockhead, forms of, 

" Height of, 

Cockle, 

" and Oat Separator,* .... 

" Machines of Cockle Separator Manu- 
facturing Company,* . 268, 269, 

" Separator Screens, Indentations in,* 

" Separator Manufactvuing Co., . 268- 

" to Remove 

" RoUs for, 

" Where Most Plentiful, 

" Screens for 257, 263, 

" Machine, 

" Machines, Capacity of, ... 
Coefficient of Friction, of Chop, . 
ofRglls, . 

Cogs, Hunting 

" Measurements for,* .... 
" for Mortise Gears, .... 



256 
41 
257 
265 
256 
256 
164 
171 
228 
315 
335 
96 
359 
429 
436 
452 
441 
442 
442 
449 
437 
443 



483 
450 
437 
435 
433 

443 
437 
441 
441 
437 
483 
439 
443 
484 
441 
441 
449 
322 
177 
195 
196 
197 
116 

115 
125 
116 
125 
116 
117 
117 
117 
177 
116 
32 
187 
117 
116 
117 
115 
187 
116 
117 
117 
155 
297 
308 
266 
271 

270 
271 
270 
256 
266 
257 
264 
41 
272 
331 
391 
223 
222 
221 



VI 



INDEX. 



300, 



Cross- 



W 



heat 



Coils of Belting, to Measure, 
Coil Spring, Hafner's Eureka, 
" " Automatic Stop for, 

" " for Spindle 
Coils, Steam, 
Coke, Air Required, 
Cold-Rolled Shafting, 
Cold Weather Work, Cement for, 
Color of Flour, 
Cologne Stones, 
Columns, Shafting, 
Colza Oil, Action on Metals 
Combination Dress, 
Combustion, 

" Air Required for, . 

" Chamber, 

" Gases of, 

" Imperfect, 

" Losses of, 

" Rate of, . 

" Slow, 

" Spontaneous, . 

" Total Heat of. 
Common Quarter Dress, Ifurrows 
ing Joints,* . 

" Salt in Boiler Feed-Water, 
"Common Sense" Millstone Balancing 

Device, 
Compasses, 

Complication of Hungarian System 
Composition and Structui'e of 

Berry, .... 
Compoimded Oils . 
Compound Tubular Boiler, . 
Compression in Steam Engines, 

" Coupling, 
Compromise Dress, 
Computation of Horse-Power, 
Concave Breast. (See Single Roll.) 
Concrete Filling for Floors, . 
Concave Breast with Single Roll, 
Condition of Boiler Water, . 

" of Steam Engine, . 

" of Pulley, Influence of, 
Concave Fmrows, . 
Condensation, .... 
Condenser, .... 
Cones, Iron, for Grinding, 
Cone Pulleys, Open Belts upon, 
Conical RoUs, .... 
Connections for Boilers, 
Connecting Rod (see Steam Engine) 

" of Wire Rope,* . 
Connections, Smoke, 
Consumer, McGinnis' Smoke, 
Construction, Fire-Pi'oof, 

" of Gear Teeth, 

" of MiU 

Consumption of Coal, 

" of Fuel 

" of Fuel per Hour, 

" of Lubricants, 

" of Coal by Boilers, 

" of Power by Tenants, . 
Contact Area, Influence of Belts, 
Convex JMUllng, 
Conveyor, ' aldwelPs Spiral,* 

" CoupUng, 

" Bracket for,. . 

" Double Chain,* 

" Double Flight,* . 

" Flexible Spiral,* . 

" Flat,* .... 

" Long Belts for, 

" Flat, Single Link, 

" Coupling. Bracket for. 
Cool Bolting 

" Grinding, 
Cooltng-off Boilers, 

" the Chop, 
Cooper, J. H., on BeltSpUcing, 
Copper and Tin Bearing Metal, 
Copper Boilers, 
Copperas for Rats, 
Coquelicot {Lychnis Githago), 
Cord Wood. Weight of, 
Cockhead, Forms of, . 

" Height of, . . . 
Corliss, Type of Engine Frame, 



164, 



341 
151 

309 

487 
382 

508 
247 
124 
163 
193 
337 
182 

20 
387 
154 
177 
199 
335 
177 
163 
286 
229 
284 
155 
170 
242 
126 
137 

29 

225 

9 

177 

131 

42 
244 
116 
177 
199 
283 
467 
194 
195 
217 
466 
468 
217 

29 
217 
195 
361 
387 
154 
361 
205 
249 
119 
520 
266 
117 
297 
308 
175 
of Valve Gear for Steam Engines, 161 



399, 



PAGE. 

526 

51, 252 

2,52 

251 

37 
115 
I'JO 

15 
475 
285 

19 
248 
320, 337 
114 
115 
125 
114 
115, 118 
115 
116 

32 
348 
115 



335, 

152, 



Standing oi- 



ls. 



Com, Burr for, 

" Grinding, 

" Dress for. 
Com Meal, Screens for, 
Corn MiU,* 
Corn, Screens for, . 
Com Smut, 
Cornish Boiler, 
Correct Balancing, either 

Running.* . 
' orrosion of Boilers, 

" by Soot and Ashes, 

" of Tubes, 
Corrugated Shutters, 

" Boiler Flues, . 
Corrugations of Rolls, . 

" Depth of, 

" Fineness of, . 

" li'orms of, 

" Number of, 

" Round, 

" Sharpness, 

" Shallow, . 
Corundum Wheel Dresser, 
Cost of Altering, 

" of Building Biurs, . 

" and Depreciation of Machinery 

" of Dressing Burrs, 

" of Excavation, 

" Cost of Facing and Furrowing. 

" of Fifty Horse-Power Steam Engine 

" of Fuel 

" of Fuel per Barrel of Flour, 

" of Hauling, .... 

" of Manufactiuing Flour, 

" of 100 Horse-Power Engine, 

" of Putting in Steam-Power, 

" of Wheat Transportation, . 
Cotton Factories, IiTegular Motion in, 

" Belts, 

" Waste, Danger from Fire by, 
Couch, A. B., on Belt Transmission, 
Coupler, Conveyor, 

" Spiral, 

Coupling and Bearing for Conveyor,* 

" Compression, .... 

" Gudgeon,* .... 

" Flange, 

" Plate 

Couplings for Shafting, . 

Covering, Air Space for Pipes and Boilers, 

" Forebay, 

" for Boilers, .... 

" for Pipes, .... 

" for Pulleys, .... 

Cowls 

Cracking Burr Faces, . . 336, 

" Picks, 

Crane Irons for Burrs,* . 
Crank of Engine, . . . 

Crank-Pin, 

Crawinkler Stone, .... 

Cream-colored Bm-r, 

Cresson, G. V., Turned Wrought-Iron 

Shafting, 
Cribs for Flumes, . 
Cross-Head of Steam Engine, 
Crossed Belts, . • . . 
Crossing Angle of Furrows, . 



125. 



381. 



189, 



1.34 



18. 
144, 353. 



324, 328, 



PAGE. 

288 
343 
842 
262 
60 
204 
518 
122 

310 
150 
1.54 
131 
20 
122 
395 
392 
390 
391 
395 
390 
392 
394 
337 
482 
318 
522 
318 
11 
.318 
185 
75 

, 186 

3, 10 
.523 
185 
185 
525 
178 
200 
32 
197 
194 
195 
194 
193 
196 
194 
105 

, 193 
140 
106 

, 145 
145 
235 

, 137 

, 3S1 
345 

, 317 

, 171 
170 
288 
288 

188 
105 
170 
199 
330 



DAMP Bran, Danger from Fire by, . 33 

Damp Smut, Danger from Fire by, . 33 

Damsels,* 314, 315, 316 

Dane Bail and Driver,* .... 305, 300 
Danger from Fire tlirough Elevator 

Heads 31 

" from Lights 29 

" of Overloading Safety Valve, . . 141 

Dangerous Oils 247 

Dark-colored Biu-rs, 288 

Day's Work Lathing, 22 

" of Plasterer, .... 22 

Decked Penstock,* 101 

Definition of Glutenous, .... 379 

" of Processes, 380 

Deflection of Wire Ropes 239 

Deflecting Plates for Boilers, . . . 138 

Degermination. Ideal,* 372 

Degerminator Mills,* 370 



INDEX. 



Vll 



Elements in, 

Evans,* . 

First, 

Hollandisli Circle, 

Improved Circle 

Jones, 



63 



508 
522 
392 
335 
3:35 
354 
, M 
216 
448 
383 
386 
176 
510 

21 
177 

71 
358 
137 
250 
389 
188 
355 
354 
354 
515 
337, 338 



447 



161, 17' 



Delacroix, V. S., Composition and Struc 

ture of Wheat, . 
Depreciation of Machines, etc., 
Depth of Corrugations, . 

" of Furrow for Middlings, 

" of Furrow for 'Wheat, 
Dessau, Black Diamonds, 
Deseronto MUl, Noyes & Sons' Plan of,'' 61 
Detachable Link Chains, 
D6tacheurs,* . * . 
Details of 150-bbl. Roller Mm, 

" of Rollers and Frames, 
Detroit Cyhnder Lubricator, 
Dextrine, . 
Diagonal Sheathing, 
Diagrams, Indicator, 

" Milling, . 
Diameter of Burrs, 

" of Chimneys, 

'■ of Journals, . 

" of Rolls, . 

■■ of Shafting, . 
Diamond Dresser, Benton,* 
Dessau, 

" Dressing, 
Diehl Wheat Starch,* . 
Dickson Dress,* 

Differential Block, AVeston's,' ... 469 
Differentially Speeded Saw-Tooth Rolls,* . 392 
Dimensions of Turbines, ... 91 

Direction of Furrows 333, 352 

Dirt, Reels for,* ... . . 443 

" in Wheat, Quantity of, . . 254, 256 
Discharge of Water from Turbines or Wa- 
ter- Whe^s 82 

" Velocity of Water. . . 107 
Disc MiUing 283, 284 

" Mills, Iron,* 286, 367 

'• of Raymond Brothers' MUl,* . 868 
Discs, Cast-Iron, 285 

'• Ideal Action of,* . . . 372 

•" Porcelain Block, 283 

Disintegrators. .... 257 

Distance between Gear Teeth, 225 

" " Hangers, .... 191 

Pulley Centres, . 199 

Grate Bars, . . 132 

" of Transmission by Wire Ropes. 237 

" between Shafts, 202 

DistUlery Slops for Scaling Boilers, . . 153 
Distribution of Chop by Furrow, . 331 

Dixon Crucible Co., Lubricant, . . . 245 

Domes, Steam,* 129 

Doors, Furnace, 137 

" Iron, 20 

" Trap, .... 
Dormant Flour-Packing Scale,* . 470 

Double Belts, .... . . 201 

" Chain Conveyor,* . . . 217 

■■ FUght Conveyor,* .466 

■ Turbine, ... . . 95 

Dough from Flom*, , ... 476 

Dowel Joints,* .... 497, 499, 500 

Drab Burr-Stone, 

Draft of FmTows, 325 

Hughes' Rule, ... 333 

" Furrows with Equal, .... 327 

" Regulator Preventing Smoke by, . 142 

" Square Using,* .... 352, 353 

" of Furnace 115, 131 

•• Area of Boiler Tubes, .... 127 

■■ Regulator, . ' 142 

'■ Tube for Turbines, ... 94, 106 
Draught. (See Draft.; 
Dress, 

■' Amdt, . . . 

" Bowman, 

" Choice ol^, 

" Circle Quarter,* 

'■ Combination, 

' ' Compromise, 

" for Corn Grinding, 

'• Cm-ved, 328, .329. 

" Dickson, . 



320, 



324 
340 
;339 
319 
32.5 
327 
337 
342 
330 
338 
320 
328 
344 
327 
327 
338 



326, 



Fur 



Dress, Logarithmic Spiral,* . 

" For Lower Runner for Rye, 

" for Middlings Grinding, 

■' New Circle,* .... 

" for New Process Wheat Grinding, 

" New Style Equalizing, 

" for Old Progress WTieat Grinding. 

'■ Old Style Equalizing, . 

" PaUet's 

" Pennsylvania and New Jersey, 

" Quarter, 

" Eye Grinding, 

" Sickle 

" for Upper- Rxinners, 

■• for Under-Runner for Wheat, 

" Wiebe's,* .... 

■' Wrong Arrangement of Short 
rows for Quarter,* 

■ ' (Look also under sub-heads as Circle, 
Wheat, Rye. etc.) 
Dresses, Test with Various, 

" Various, . 
Dressers, Coriuidum Wheel, 

" Emery- Wheel, 
Dressing,* 

" Burrs, 

'• Kaestner Burrs,* . 

'■ Cost of, . 

"■ Diamond, 

" Position in, 

" for Regrinding, 

•■ Stone, 
Driers, .... 
Drift-wood, to Keep out of Fli 
Drive, Stiff v. Oscillating 
Driver 

" Dane,* 

" Mortise for. 
Driving Irons, Forms of,' 

" Power of Pulleys, . 

" " of Single Leather Belts, 

'■ PuUeys, Hafner's Equilibrium,* 

" Bopes, 

" Side of Belt, . 

'■ Two Lines of Burrs from One Shaft, 
Drop-Lift Step,* 
Dry Grain. Burrs for, 

" Leather Belts, 

■' Peat, 

" Steam. 

Economy of, 

" Pipes for BoUers,* 

" Wood, 
Drying and Heating Wheat, 
Duplex Safety Valve, 
Durant, W. N., TaUies, 
Duration of Belts, . 

" of Wu-e Ropes, 
Dust Collector,* 

'• Effect of, in Mill, 

'• to Take Out, . 
Duty of Cornish BoUer, 

" of Hands, 

" of the Furrows, 
Dynamometer, 



EARTH Oil for Scaling Boilers, 
, Eccentric Straps, . 
Economic Flour Packer, 
Economy of Dry Steam, 

'■ of Heating Feed-Water, 

■' of High Pressure in Steam Engi 

" of Steam Engines, 

" Measure of, 

Edge Blocks 

Eels in Turbines, .... 
Effects of Heating on Boiler Plates, 

Electric Light, 

" In-egular Motion for, 

" TaUy,* 

Elements in a Dress, 

" in Belt Transmission, . 
Elephant Boiler, .... 
Elevator, Atr-BIast. 

" Boot,* 

" Bucket,* .... 

" Driving Chains, 

■' Grain. End View.* 

" Heads, Danger from Fire, . 



PAGE. 

327, 328 
340 



342 
329 
342 
337 
342 
337 
342 
337 
337 
342 
326, 337 
335, 330 
340 
329 



328, 



128, 



477, 



328 



335 
342 
337 
337 
350 
344 
377 
318 
3M 
347 
341 
15 
28 
106 
303 
305 
306 
301 
313 
235 
201 
253 
239 
202 
211 
434 
288 
200 
115 
138 
164 
138, 139 
115, 116 
279 
141 
479 
200 
239 
413 
24 
255 
122 
521 
322 
177 



153 
173 
477 
164 
147 
1G2 
185 
162 
289 

96 
120 

38 
178 
479 
320 
199 
122 
459 
455 
450 
217 
460 

31 



478. 



458, 
454, 



Vlll 



INDEX. 



PAGE. 

Elevator of Niagara Falls Mill, ... 50 

" Pulley, Danger from Fire, . . 31 

" Cost and Depreciation of, . . . 523 

" Detachable Chains for, . . 219 

" Speed of, 219 

Elm, 116 

Embiyo 513 

Emery \V'heel Dressers, . . . 337, 356 

Ended Wheat, Reels for,* .... 2G5 

Ending Reel, 25' 

" Stones, 257, 266 

" " Flour from, .... 257 

Endocarp, 513 

Engine, Steam, Automatic and Slide- Valve 

Compared, 186 

" Care of, 173 

" Crank Pin of, 170 

" Cranks, Cast-iron, .... 170 

" Friction of, 161 

" Guides of, 169 

" Horizontal 175 

" How to Order, 39 

" Rating of 177 

'■ Regularity of. Speed, .... 165 

" Rmming Away of, . . . 167 

'• Rmming. Check upon, . . . 177 

" Buying Steam, 185 

" Care and Management of, . . . 174 

" Economy of, 185 

" Fast-Running, 164 

" Guarantee of, 185 

" Improved, Non-Condensing, . . 178 

" Lubricating 170 

" Non-Condensing 161 

" Speed of 164, 105, 175 

" Size of 175 

" Cut-off 164 

" Stroke of, 169 

" Throwing Over 169 

" Wheelock 179 

Enlargement of Mills, 11 

Epernon Stone 288 

Epicarp, . . • . . . . 513 

Epicycloid Teeth 221 

Epispenn, 513 

Equal Draft for Furrows.* .... 327 

Equally-Speeded Saw-Tooth Rolls,* . . 393 

Equilibrium, 306 

•' Stable.* 307 

" Unstabled,* 307 

Ergot, 513, 519 

Esopus Stone Quarry,* .... 292, 393 

" Stones 285, 288 

Estimates, 39 

Eureka Coil Spiing,* .... 251, 252 

Erysiphe Graminis, 519 

Evans' Dress,* 328, 329 

' OUver, Model Mill of 1790,* . . 69 

Evaporation of Mineral Oils, . . . 248 

" of Water 116 

Ewart Driving Chain,* 216 

Excavation, Cost of, 11 

Excelsior MiU, Plans of,* . . . 54, 57 

Exhaust, Behms Brehmer,* . " 363, 364 

" Closiu-e of, in Steam Engine, . . 177 

" for Millstone, 335 

" Steam for Feed-Water Heating, . 149 

" " for Heating Boiler Feed-Water, 147 

Expansion, Actual Rates of, . . . 159 

Joints for Steam Pipes, . . . 138 

" of Burr, 359 

" of Flues 126 

" of Iron Beams, 19 

" Rates, 160, 184 

" Regular, 159 

" of Spindle, . . . . . . 3.59 

" of Steam, 158 

" Trap 145 

Experiments Concerning Boiler Covering 

at Newton's Tool Works, . . 146 

Expert Advice Concerning Boilers, . . 153 

^- Tests 177 

Exports, Use of, 179 

Explosion of Mills, 361 

" of Reels 33 

" Precautions against, .... 33 

" Windows to Lessen Effects of, . . 38 

Export, Flour for, 279 

External Corrosion of Boilers, . . 150 
Extinguisher, Chemical, . . .37 



Extinguisher, Fire, 
Eye of Burr, . 

■' Clogging of, . 
Eyeless Pick,* 
Eye Blocks, 



PAGE. 

29, 37 



331, 



303 
359 
346 
295 



Ij-^ACE 

J' Facingand Furrowing, tost of, 
"Factor of Hoi-se-Power,"' . 
Fairbaim Boiler, .... 
Fall of Water, 

" for Hydraulic Ram, 

" for Overshot Wheel, 
FaU River, Cost of Steam Equipment, 
Falls, Low 

'■ High 

Fan-Blast Attrition MiU,* 

Fast Grinding, 

" Ruiming Macliinery, Shiftei- for, 

" Running Engines, . 
Fastening Boiler Tubes, . 

" the Rynd and Driver Boxes, 
Feather-Edge, 

" Depth of, .... 
Feed Pipe, 

" Pump, Where to Put, . 

" SUent,* 

" Water for Boilers, Economy of Heat- 
ing, 

" Water, Temperature of, 
Hard, 

" " Fresh, 

" " FUtering 147, 

" " Impurities in, . . 147, 

" '■ Heaters for Boilers,* 139, 

" " " and Purifier, Steam 

Jacket,* . 

" Water Heater for Lime, 

" " " Back Pressure from, 

" " " Baragwanath's, . 

" " Heating by Waste Steam, 

" " Table Showing Economy of, . 

" " Nystrom on Percentage of 
Saving' ... . . 

Feeding Various Materials 

Felt Lagging for Steam Engines, 

Ferrules, 

Fifty Horse-Power Steam Engine, Cost of, 

FUes, to Use 

Filling Boilers, 

" Frame Walls, 

Filtering Feed-Water, .... 147, 
Fineness of Roller CoiTugations, . 
Finger Coupler,* ... . . 

" Clutch,* 

Fire-Box, Height of, 

Fire-Brick Partitions, 

Fire Extinguishers, .... 29, 

" Extinguishment, Steam Pipes for, . 

" Loss from in Yae^er Mill, . 
Fire-Proof Material, Bricks Considered as. 

" '■ Construction, .... 

" " Floors, 

Fire Surface, 

" Temperature of, 

Fires and their Causes, 

Fire, Danger to Roofs by 

" Danger from, through Elevator Pul- 
leys 

" from Damp Pan, Soft Coal. Candles. 
Smut, Spontaneous Combustion, etc , 

" through Coal Dust, Flour, etc., . 

" Precautions against 

" Months in which MiUs Bum, 

" Prevention of 

" Protection from 

" Protection from, in the Washburn A 
MUl 

" Slicing of, ... . 
Firing, Economy of Careful, 
First Dress 

'• Roller Mill 

Fitting a New Back 

Five-Run MiU, Sections of.* . 

Fixed Water-Pipes, 

Flame 

Flange Coupling, 

Flanks of Gear Teeth 

Flashing Point of Lubricants. 



332 
318 
183 
122 
107 
3U 



103 
103 
366 
359 
215 
164 
130 
302 
330 
335 
143 
143 
314 

147 
143 
147 

147 
148 
1.50 
149 

149 
153 

149 
148 
149 

148 

147 
315 
165 

130 
185 



155 

21 

148 

390 

165 

195 

135 

30 

37 

37 

30 

29 

29 

20 

127 

117 

31 

23 



31 



33 

33 
31 
29 
;34 

31 
118 
119 
344 
382 
317 
65 
37 
114 
194 
225 
247 



INDEX. 



IX 



.„ PAGE. 

Flat Arches 20 

• Belt, Pulleys for 839 

■■ Grinding 380 

Flaxseed. Screens for, , . . . 26-3. 264 

Flesh Side of Leather Belts 199 

Flexible Spiral ConTevor. * . 467. 468 

Floats. Shape of. Water- Wheel, ... 77 

■" Measurement of Water-Power by, . 110 

Flood-Gates 106 

Floor Beams, Support for 19 

■• Plans 19 

Floors 19 

■• for Storage, 20, 481 

'" Concrete Filling for 20 

'■ Fire-Proof 20 

" Mill 11 

Flour, Coal per Barrel of 187 

■■ Color of. 360. 390, 475 

■• Cost of Fuel per Barrel of, . . 186 

" Danger from Fire by 32 

" Dough from 476 

" Jlills, Dust causing Explosion of, , 361 

" from Ending Stones 257 

" Feeding, 315 

" Granular 360 

" Overheating 359 

Flour-Packer, Economic 477 

Flour-Pacldng Scale, Dormant, . . . 470 

Flour. Power Required per Barrel. . . 76 

" SaTing 362 

" Specky 333, 336, 432, 436 

'• Storage of, 476 

" Strength of 476 

" Strong • . . 517 

" Testers,* 475 

" Trier and Inspector, .... 475 

" Yello-B- .360 

Flouring Machinery, Belts upon, . . 202 

Flow of Material 11 

" of Water in Turbines,* . . .81, 82 

Flues of BoUers, 126 

" Expansion of, 126 

Flue Cleaner, Chalmers-Spence,* , 153, 154 

Flutter Wheel, 77 

Flumes for Turbines, . . . .13, 92, 94 

" Area of 100 

" Building 100 

" Cubes for 105 

" Position of 100 

" to Keep Driftwood out of, . . . 166 

" Weight of Water in 103 

" with Victor Turbine 92 

Flume, under,* 104 

Fly-"\\Tieel, 168, 201 

" upon Line Shafting, .... 194 

Foaming in Boilers. . . . 125, 142, 155 

'■ Cause and Remedy of, ... 138 

" caused by Scale 148 

" caused by Sulphate of Lime, . . 153 

Force, Centrifugal,* 307 

" " in Burrs, .... 332 

" Tangential,* 307 

Forced Draft 115, 132 

Forebay Covering, 106 

Forms of Cockhead,* 297 

'■ of Corrugations 391 

of Dri\-ing Irons,* . . . : . 313 

Foresfs M illin g Diagram 71 

Foundations for Boiler Setting, , . . 134 

'• MiU 12 

Foundation of Steam Engine. . . 167 
Four Hundred and Fifty Barrel Roller 

Mill. Belting System for. ... 385 

Four Hundred and Fifty Barrel Burr Mill. 42 
Four Hundi-ed and Fifty Barrel MiU, 

Building for 41 

Frame Buildings. Sheathing for, , . . 21 

" for Engine, Corliss, , , , . 175 

'■ Walls. Filling for 21 

Framing an Overshot, 506 

Franklin Institute Tests of Steam Engine 

Governor 167 

French Windows, 38 

'■ Boiler 135 

Fresh-Water Feed 146 

Freshets 106 

Freshly-Cut Wood 116 

Friction and Lubrication 243 

" Angle of the Chop, . :3.30, aSl 

" Brake 177 



328, 



Friction Clutch. Hafner's,* 

■' Coeiiicient of Chop, 

■' Drive for Rolls, 

" of Engine, 

" of Journal, 

" of Belt. . 

" Pulleys. . 

" Tractive Force of, 

" Rolling. . 

" Sliding, , 

" Solid, 

" Water-Wheel Governor,* 
Frost, .... 
Fruit Coats of Wheat, . 
Fruits for Scaling Boilers. 
Fuel, Consimiption of, . 

'■ "■ per hour 

in 250-Barrel MUl, 

■■ for 100-Barrel Mill, 

" Required for Two-Run Burr Mill, 

'■ Cost of " 

" per Barrel of Flom-, Cost of, 

" Loss from Unbumed, 

" Minnetonka MUl, Amoimt Consumed 
in 

" Moisture of , . 

" Qualities of, . 

" Waste of. 

Fuels 

Function of Lubricants, 
Furnace 

" Doors of. ... 

■■ Height of , 

" HoUow Walls for, 

" Radiation from, 
Fmrows, Action of, 

" Angle of Crossing,* 

" Bent,* , . . . 

" Circle or Circular. 

" Concave, 

" Curved 

" Crossing. Angle of. 

" Direction of, . 

'' Draft of 

'■ Duties of, . . . 

" Hollow 

" with Equal Draft,* 

" Grain of Wheat in,* 

" Gouge 

" and Lands, Smoothness of, 

" Laying Out. . 

'■ Circle. Laying Out, 

" Logarithniic, Laying Out, 

" Number of . . 

" Number of Parallel. 

" Outline of. 

" Radius of, . ' . 

" Rectilinear, . 

'■ Reversed. 

" Sheaiing Action of , 

" Spiral 

" for Hard Wheat, . 

" for Middlings. Depth of, 

" for New Stock Burrs, . 

•' for Porous Stone. . 

" for Soft Wheat. . 

" Ventilating Action of, . 
Furrow for Wheat, Depth of, 

" Section, Proper,* . 
Wrong,* . 

" " for Low Grinding, 

" Strip 

" Sm-face for Close Stones. 

Fusible Plug 

Fu2z to Remove, 
Furring of Gauge Cocks, 



PAGE, 

196, 197 

331 

286 

161 

243 

200, 203 

235 

234 

343 

243 

243 

97 

14 

513 

153 

131 

42 

187 

186 

42 

75 

186 

115 



:2S, 



187 
117 
117 
117 
117 
244 
114 
1.37 
125 
115 
115 
334 
3.30-^3:32 
324, 325 
324, 326 
:335 
324 
330-332 
333, 352 
25, 333 
322 
2-35 
327 
322 
335 
336 
351 
•3;33 
325 
324 
323 
.324 
333 
334 
323 
332 
325 
322 
a35 
324 
.324 
322 
332 
;33.5 
33G 
336 
335 
.352 
322 
141 
255 
152 



332, 



.323. 



r^ ALLOWAY Boiler 122 

Vjr Gallons in Tanks .34 

Galvanic Action Causing Boiler Corrosion. . 150 

Gardner's Steam Engine Governor,* . lOfi, 167 

Garlic 257 

" How to Take Out 41 

Gas Coal 117 

Gases of Combustion 114 

'■ Illuminating 38 

Gate, Register for Turbine.* .... 88 

Gates, Water 34 

Gauge Cocks 155 



INDEX. 



Gauge Cocks, Furring of, 

" Glass Water, 

Gauge Pressures, 
Gauges. Pressure, 

" Oscillation of Water in, 

" Velocity, . 
Geared Under-Runner Mill,* 
Gearing 

'• Bad 

" Badly Designed. 

" for Water- Wheels, 

" How to Order, 

" Poole & Hunt's. 

" Transmission by. . 
Gear Teeth. Breadth of, 

" Construction of, 

" " Distance of. 
Flanks of, . 
" Laying Out. 
" Shoulders of, 

" " Thickness of, 
Gears, Cast, 

" Cogs for Mortise, . 

■' Cut 

' for Roller Frames, 

" Involute,* 

" Moulded Cast, 

" Mortise, . 

'■ succeeded by Belts, 

" Wooden, . 
Gear Wheels, Backlash from 

" Backlash of Involute, 

" " Bilgram's Method of Laying 
Out. 

" " Calculations, . 

" " Cleaning Curve of. 

" " Laying out Involute, 

" " Thickness of, . 

" " Velocity Ratio, 
General Idea of Sheave for Wire Rope, 
General Section of Mills" Machine.* 
Generators for Steam Wheat Heaters 
Geology of La Fert6, ... 

Georgia Burr, 

Germ. Analysis of, . 

German Burr, 

" Wheat, Analysis, . 

Germ Rolls, 

Glass Gauges for Boilers, 

■■ Millstones 

'■ Water Gauge, . 

Gliadin, 

Globes, Calculations of. . 

Glue for Belts, 

Gluten, ..... 

" Percentage, .... 

'■ Sacks 

Glutenous. Definition of. 

Gouges, 

Gouge Furrows 

Governor Steam Engine, Automatic 

for 

Governor Centrifugal, . 

" for Water-Wheels, 

" Gardner's Steam Engine,* . 

" Steam Kngine, 

" Tests, 

" Water-Wheel,* 

Grader,* 

Gradual Reduction JIachine, Mills' En 

larged Section 

Gradual Reduction on Burrs, 
Gradual Roller Reduction, Heaters, . 
Gradual Reduction. (Look under sub 
heads Granulation, Rollers, Jona 
than Mills, etc., 
Grain Cleaning, .... 

'• Destroyers. Chapter on, 

" Elevator, End View,* . 

" of Wheat in Furrows,*. 

" Side of Leather Belt, . 

" to make Musty, Sweet, 

" Weevil 

Granite Burrs 

Granular Flour 

Granulation (see sub-heads Grinding 
Graphite as Lubricant, . 

'■ for Hot Bearings and Journals, 

" for Wooden Bearings, . 

" in Steam Cyhnders, 



Stop 



&c. 



PAGE. 

152 
141 
155 
141 
122 
107 
374 
220 
75 
177 
86 
40 
220 
220 
2-,i6 
225 
225 
225 
220 
225 
225 
220 
221 
220 
389 
226 
220 
221 
199 
221 . 
251 
228 

220 
137 
228 
227 
226 
225 
239 
.371 
280 
291 



510 
288 
511 
482 
155 
284 
141 
509 
537 
205 
507 
517 
513 
379 
488 
335 



166 

lf)5 

96 

166, 167 

165 

166 

97 

274 



371 
330 

281 



253 
518 
460 
322 
202 
254 
519 
288 
360 
357 
245 
244 
245 
176 



PAOE. 

Grate Bars, 131 

Distance of, 132 

" Shallow 132 

'• Length of 125 

•• Surface 123, 131. 132 

Watt's Rule 131 

Gray Burr 288 

Gravel in Wheat . 254 

Gray. W. D.. Roller Frames,* . 402, 403. 404 

Green Timber 19 

Grinding 357 

•• Cool, 335. 387 

" Coolness of, 387 

" Corn, 343 

'• Fast 359 

'■ Flat, . . 380 

" Furrow Section, for Low. . . . 335 

" Hard Wheat. Dress for. . 342 

•' High 380 

" Middlings, 343 

" Picks, 345 

" Soft Wheat 361) 

•' Soft Wheat, Dress for 342 

" Speed of . . 359 

" Troubles in, 359 

" Wheat 295 

Grit in Steam Chest caused by Scale. . . 148 

Grip of Belts. Tests of 207 

Gross Power of a Water Fall, . . . Ill 

Grooved Chilled-Iron Rolls, . . . . 287 

Grooving of Boilers 151. 126 

Grubs, to Prevent, -'129 

Guarantee of Steam Engine, ... 185 

Gudgeons. 505 

Gudgeon. Coupling for, 190 

'■ Plate 196 

" Wing 196 

Guides of iSteam Engines 169 

Gum in Wheat 510 

Gumming of Burrs, 257 

"■ of Lubricants, . . . . . i45 

Gyration, Radius of, 309 

HAFNER, J. A., Equilibrium Driving 

Pulleys.* 253 

Hafner's Eureka Coil Springs,* . 252 

Hafner Friction-Clutch 196 

Hairs of Wheat Berry.* 5lS 

Hair-Felt Boiler Covering 146 

Hair for Plaster 28 

Half -Twist Belt,* 213 

Halving Together,* 492 

Hammers, 4S7. 488 

Hancock Inspirator,* . . . . 143. 144 

Hand-Block Rubber,* 356 

Handles for Picks 347 

Hangers for Shafting 191 

'■ Distance between, .... 191 

Hanging of Boilers, 137 

Hard Spring Wheat, Rolls for, ... 395 

'■ Maple Wood 117 

Hardening Steel, 345 

Hard Wood 116 

Hardness of Wheats 523 

Hard Finish for Walls 21 

" Water for Feed 147 

■• Wheat -389 

" Furrows for, .... 322 

" Grinding. 279 

Harris Safe Works. Magnets of, . 2.55 

Harleigh Lehigh Coal, 116 

Harrington & Oglesbv, Grading Screens 264 
Hauling, Cost of , . . . 12. 15, 16 

Heads of Boilers, Thickness, . . 123 

Head Race. Area of . . . . 100 

Heat, Available 114 

'■ Latent 157 

" Sensible 157 

" Total of Combustion 115 

Heat Units, 115 

Heating of Belt 203 

" of the Chop, . . . 322. 325, 343, 3B1 

" of Eccentric Straps, .... 173 

" Feed-Water,* . . 139, 147, 119 

" Feed-Water by Waste Steam, . 149 

" Surface of Boilers 123 

" Surface, Square Feet for Mills. . . 37 

Heaters (Wheat), Steam Generator for,* . 280 

" Thermometer Attachment for,* . 281 



\ 



INDEX. 



Ed 



Heated Wheats, to Purify, 
Heating. Value of Wood, 
Heavy Side of Burr, Tendency of the 
Height of Building, 

" of Cockhead, 

" of Fire-bos, . 

" of Furnace, . 

" of Roof. . 
Helps to the Miller, 
Hemlock Bark for Scaling Boilers, 
Herschel. C. Tests of Turbines by. 
Hickory Wood. 
Higgins, John C, Mill Picks, 

High Falls 

■' Wood Flume for,= 
High Heads for Turbines, 

"■ Grinding, 

•' Water-Falls, . 
High Pressure, Aspiration. 

■■ Pressures causing Leakage, 

Economy of , in Steam 
gines. 
High Pressure Steam, . 

" Steam Engine, 

" " " ■■ Scale from 

" " Tables Showing Saving in 

Steam Engines by use of, 
Hodgkinson Beam, 

Hoisting Irons 

Holes in Walls 

Hollandish Circle Dress, . 

Hollow Birch Partitions. 

■ Brick Walls. . 

•■ Furnace Walls, 

■• Furrows 

■ " Shafting 

■ ■ Walls for Boiler Setting. 
Holyoke Flume. Tests in. 
Hominy. Screens for. 

•■ System of Clearing, 

Honey Dew 

Hoops. Barrel 

■ Bowling, . . 
Hopper. Setting, Bevels,* 

"" of Grays Roller Frame, 
■■ Scales.* .... 
•■ Capacity of, . 
■" Frames. . 
Horizontal Belts. 
■■ Cylinders. 

■ Cylinder Boilers, Laterally 

■" Engine 

■' Externally Fired, Boilers. 

Horse-Power of Belt. 

" Computation of, 

" " Factor of. . 

" Mark's Formula for. 

" " of Wire Ropes, . 

Horsford's. Professo"". Analysis of Wheat Ash 
Hose, New York Belting and Packing 

Company's.* 

Hot Bearings 

Hot-Rolled Shafting 

Hughes' Rule for Draft of Burrs, 

Hulling. Stones for, 

Hundred Horse-Power Steam Engine, Cost 

of 

Hundred and Fifty Barrel MiU, . . 3a3. 
Hungarian Burrs 

■■ Roller System 

'' System. Complication of. . 

•• ^Tieats, 

Hunting Cog, . , 

Hursts 10. 311. 

■ Iron. 

Hs'drants. . . . ' 

Hydraulic Lime in Mortar, .... 

'" Ram, 

" " Capacity of, 

•• Fall for." 

Hydrogen. 

■■ Burning of 

Hydrogenous Coal 

Hyperbolic Logarithms, . . IS!*. 
Hyperboloid Rolls, 



Kired, 



PAGE 
254 
117 
.310 

10 
308 
135 
125 

22 
521 
153 

87 
116 
346 
103 
104 

94 
380 

95 
362 
171 

162 
126 

162 

163 

18 

317 

19 

327 

17 

29 

115 

335 

191 

134 

86 

264 

265 

.=>18 

476 

126 

500 

104 

471 

526 



1W9. 



296 
202 
169 
122 
175 
134 
201 
182 
183 
183 
2.37 
511 

35 
244 
190 
333 



185 

3S4 

288 

.3.S0 

382 

.382 

22:3 

296 

11 

34 

17 

.35 

3h 

36 

114 

115 

117 

160 

284 



ICE in Water- Wheels 
Ideal Action of Discs for Splitting and 
Degermination.* .... 



372 



PAGE. 

Idle Pulleys 243 

Dluminating Gas 38 

Imperfect Combustion 115, 118 

Impurities in Lubricants 244 

Inclination of Boilers 137 

Inclined Belts 199 

Incrustation of Boilers 151 

India-rubber Packing 171 

Indicator Diagrams 161. 177 

from Wheelock Engine 

at Cincinnati Exhibition,* . 178 

Initial Steam Pressure Required. . . . 184 

Injector 143 

Insect Powder. Persian 520 

Inspection of Bran 475 

" of Flour and ileal 475 

" of Wheat Cleaning Machinery. . 11 

Inspector and Flour Trier,* .... 475 

Inward Flow Turbines 81 

Inspirator. Hancock 143 

Internal Corrosion of Boilers. ... 150 

Internally Fired Boilers. ... 122 

Involute Gears. Approximate.* . . . 226 

Irregular Motion, 178 

•• Power 199 

Iron Beams. ... ... 30 

"■ Expansion of 19 

Iron Bearings 249 

■ Burr Crane 317 

•" Cones for Granulating. . . 286 

■■ Disc Mills.* 286, 367 

• Doors 20 

■ Hursts 11 

" in Wheat 254 

■' Jackstick. with Level.* ... 299 

" Oxide in \Vheat 511 

■'■ Paint-Staff,* 348 

■■ Penstock.* 90 

'■• Roof, ... ... 23 

" Sashes -^ 

■' Water in Boilers, 152 

" Windows 20 



TACK, Reel,* 

»J Jacket, Steam, 

Jackstick, Iron, with Level.* 

Jersey Pine as Fuel. 

Jet Condensers. Evils of. 

Joints of Boilers, 

'■ of Millstones. . 
Jonathan Jlills' System, 
Jones' Dress.* .... 
Single Roller Sy.stem. . 

" Cost of Making Flour by, 
Jones, Ballard &. Ballard Singln 

Mills 

Jonsdorfer Stone. . 
Journals. Diameter of, . 

" Boxes for. 

" Friction of. . 

" Stiffness of. 
Jumping of Millstont-s . 
Jute Sacks for Flour, 



29T 



:i83, 



allt 



19; 



434 
164 

299 
117 
150 
126 
290 
385 
a38 
385 
524 

.387 
283 
250 
193 
243 
250 
96 
476 



KAESTNER Vertical Burr Mill.* . . 377 

Katzenstein Piston-Rod Packing, . 171 

Kerosene as a Lubricant, ... . 245 

Kevs in 

•"• for Shafting 198 

Key Seats in Shafting 193 

Kiln Dried Lumber, 19 

Kiln Flooi-s for Oats, .... 264 

Killing Flour 359 

Kinds of Water- Wheels T7 

Kuehne & Bryant Bush,* .... 300 



LACING Belts 20.1. 206 

Lacrosse Driver, 305 

La Fertg 284 

Geology of Manufacture of Mill- 
stones 291 

Lagging Felt for Steam Engine.'^, . 165 

•• of Pulleys 201 

'■ Asbestos for Steam Engines, . 165 

" Pulleys, 234 

■' Steam Cylinder 165 

■■ Wood for Steam Engines, . . 165 



Xll 



INDEX. 



PAGE. 

Lake Superior Water for Boilers, . . 150 

Lamps 38 

Lancashire Boiler, . . ... 12i 

Land and Furrow Surfaces, Proportion of, 322 

Lap and Lead 161 

Lard Oil as Lubricant, . ... a45 

" " Action on Metals 248 

Large Wheat. Rules for,* .... 265 

Latent Heat of Steam 157 

Lathins;, Day's Work, 'ii 

Laths for Plastering 22 

" Cover a Given Surface, ... 22 
Laterally Fired Horizontal Cylinder Boil- 
ers 123 

Lava Burrs 288 

Lawton & Arndt's Bran Dresser,* . . 426 
Laying off and Cutting the Holes in the 

Balance Rynd 301 

Laying out Belts, 209 

'■ Circle Furrows,*. . . 332, 333 

" Furrows,* 351 

" *' Gears 220 

" Bilgra'm's Method,* '. . 221 

" " Fole's. for Quarter-turn Belts * 210 

" " Involute Gear Wheels, . 227 

" Teeth of Mortise Teeth, . 222 

Lead and Lap 161 

Lead-colored Burrs, 288 

Leaders, 24 

•' Number of,* 323 

Leaks 177 

" of Boilers, 155 

Leakage, caused by High Pressure, . . 171 

" caused by Lack of Clearance, . . 171 

" of Boilers, caused by Corrosion, . 150 

Leaky Piston, 171 

Leather Belts 200 

" Castor-Oil for, ... 204 

'• Cement for, .... 205 

" Flesh Side 199 

" " Glue for 205 

'• New, ... .202 

" " Tests !309 

" To Prevent Rats Gnawing, . 204 

'■ Slipping of, .... 204 

" Lagging for Pulleys, .... 235 

Leaves in Turbines, 96 

Left-Hand Valves, 34 

Lengths of Bearings, 250 

•• of Boiler Tubes 123 

Length of Grate Bars, 125 

'■ of Rolls 389 

Le Van on Steam Domes, .... 128 

Level .487 

'■ Varying Water, 77 

Leveling Bed-Plate of Steam Engine. . . 167 

" Buns 297 

Life of a Boiler 154 

Lifting of Water in BoUers, . . . 126, 127 

Light, Electric 38 

Light Feed causing Jumping of Burrs, 96 

" Grain, to Take Out 25.5 

Lighting Mills . 38 

Lightning, Rods as a Protection Against, " . 25 

Lighter Screw,* 316 

Light Materials, Reels for,* .... 444 

Lights, Danger from, 29 

Lignite, . 115, 116 

Lignumvitas Stops, 95 

Lime in Wheat, • 511 

" ofTeil, 20 

Line Shaiting, Clutch for, .... 146 
Limestone Feed-Water. .... 147, 153 

Lime- Water Districts, Boilers for, . . 148 

■• Mortar in Boiler Setting, . . . 135 

Limy Districts, Tubular Boilers for, . . 148 

Limy Carbonates in Feed- Water. . 148 

Line Shaft, Clutches on,* . . . . 197 

Line Shafting Coupling, 194 

■■ Journal Boxes for 192 

Lining up Shafting 198 

Link Belt Drive for Rolls 286 

" Belts. Ewart's,* 218 

" Attachments for,* ... 219 

Links, Method of Coupling,* ... 216 

Linseed Oil, Action on Metals, . . . 249 

" '■ as Lubricant 845 

" for Rubber Belts, . ... 204 

Lining Wire Rope Sheaves,* .... 240 

Load, Moving, . . • 10 



PAGE. 

Logarithmic Spiral Dress,* . 325, .326, 327, 328 

Logarithms. Hyperbolic, .... 159 

Logwood for Scaling Boilers, . . . ViA 

Long Belts for Conveyors. .... 29 

•• Flaming Coal, 115 

■' Transmission, 239 

Loose Pulleys 233 

Lord, G. W.. Boiler Compound, ... 153 

Loss by Throttling and Wire-Drawing, . 161 

" in Combustion 115 

•■ of Driving Power of Belts, . . . 201 

'• of Heat by Scale 148 

" of Power through Gears. . . . 220 

" Water-Power by Breast Wheel. . . 77 

Lowell, Cost of Water-Power, ... 75 

Low Falls 102 

" Water in Boilers 154 

Lubricant, Blacklead as, ... . 245 

" Cylinder Oils as 245 

" Dison Crucible Co. 's . . . . 245 

" Graplute as a, 245 

" Kerosene as a, 245 

" Lard Oil as a, 245 

" Linseed Oil as a, 245 

" Neatsfoot Oil as a 246 

" Parafflne Oil as a 246 

" Plumbago as a, 245 

" Spindle 245 

" Sperm Oil as a, . . . . 245. 246 

" Tallow as a 245, 246 

" Value of 244 

Lubricating Steam Engines, .... 170 

Turbme Steps 95 

" Oil Cup, Sectional View,* ... 176 

" Sprockets and Chains, .... 219 

Lubrication Cylinder 175 

and Friction 243 

" Improper Waste of Power by, . . 177 

Lubricants, Castor-Oil, 245 

" Consumption of 244 

" Cylinder, 148 

" Flashing Point of , .... 347 

" for Brush Machines 245 

" for Separators 245 

" Function of 344 

" Gumming of 245 

" Impurities in. 244 

" Purity of 248 

'■ for Smutters, 245 

Lubricator for Cylinders 176 

■' Detroit Cylinder, 176 

Lugs for Boilers, 135 

Lumber. Air-Seasoned 19 

" KUn Dried, 19 

Lychnis Githago, 266 



MACHINERY, Brake for Fast Running, 215 
Cleaning for 450-bbl. Mill, 41 

Machines, Cockle, 41, 42 

Machinery. Shifter for Fast Running, . 215 

" Vibrating Horizontal 10 

Magnets of Harris' Safe Works,* . . 255 

" in Washburn B Mill 254 

Main Bearing Running Hot. ... 173 

'■ Valve. Trunnions, &c.,* . . . 182 
Malleable-Iron Driving Chain, . . 216 

Management of BoUers, Rules for, . . 154 

Man-Holes 125 

Mansard Roofs 30 

Manufacture of Burr-Stone, . . . 288 

" of Flour, Cost of 523 

Marble in Boilers, 152 

Marking off 490 

Marks, W. D 284 

" " Formula for Horse-power, . 183 
Material, Flow of 11 

" for Boilers 119 

'• of Rolls 286, 390 

" for Millstones 288 

" Supposed Path of,* . . 320, 321 

Maximum Velocity for Turbines, . . 81 
McFeely's Diamond Dresser, . . . 355 
McGinniss' Smoke Consumer,* . . 136, 137 

Meal, Feeding 315 

Mean Effective Pressure, . . 162, 183 

Measure of Economj^ of Steam Engines, . 162 
Measurement by Weirs, .... 108 

" of Water-power by Floats, . 107, 110 
" for Cogs,* 222 



INDEX. 



Xlll 



Measuring Fall and Width of Stream,* . Ill 

Mesocarp 513 

Mechanical EfCect of Steam, ... 157 

Mfege Mourifes 509, 513 

Mending Burr Faces, 354 

Magnesia in Wheat, 511 

Metal, Anti-friction 193 

■' Babbit, 240 

" Bearing 243 

" Copper and Tin Bearing, . . . :i49 

" Packing,* 172 

" Roofs, Protection for against Light- 
ning 26 

" Rings for Engine Packing, ... 171 

Method of Coupling Links together,* . . 216 

" of Driving Gray's Roller Frames,* . 403 

" of Driving Rolls 286, aB8 

■' of Driving Two Lines of Burrs from 

One Shaft.* 211 

" of Suspension,* 313 

Michigan Wheat, to Treat 257 

" WiQter Wheat, 523 

Middlings-Burrs, Speed of, . . . . 482 

Middlings, Clogging of, 335 

" Danger from Fire by Spontaneous 

Combustion, 33 

" Feeding, 315 

" Grinding, 343 

" Grinding Dress for, .... 342 

" Making 341, 359 

" Percentage of Products in Roller, . 381 

" Reels for,* 2BB 

" Rye 422 

■■ Screens for, . . . . - . . 262 

•■ Stone for, 287 

MUdew, 518, 519 

Mild Steel BoUer Plates 119 

Mill Buildings, Construction of. . . . 9 

" Floors, 11 

" Foundations, 12 

Mills, Explosion of, through Flour Dust, . 361 

•' Heating 37 

" Height of Washburn, .... 11 

" Lighting, 38 

■' Oscillation of, 10 

" Positions for Clearing Machines in, . 41 

" Position for Scalping Reels in, . . 42 

" Posts in, 14 

'• Sagging of, 19 

■■ Vibrations of, 10 

Mill-Dust, Effect of, 24 

MUlingCoru 283 

Milling Diagrams, Forrest 7 

Noyes & Sons. ... 73 

" " Novelty Iron >Vorks,* . 73 

Milling, Disc, 283, 284 

" Plane 283 

MOlstone. iSee also Burr-Stone.) 

Mil] Spindles, Oiling 317 

Jlillwrighting Chapter, 487 

MiU, Coal for 300-barrel, .... 187 

■' Hursts, 10 

" Magnets in,* 255 

" Ofaces, Nordyke & Marmon Plan of 70 
" Oscillating Under-Runner, horizontal. 285 

TJpper-Runner, ■" 285 
. " Smallest Roller that will Pay to Put 

up 42 

■' Rigid Runner Horizontal, . 285 

'• Turbines of Niagara Falls, ... 48 

" Vertical, 286 

" Plans, 41. 42, 71 

Allis 42. 47 

" " Circumstances which Deter- 
mine 9 

" 450-barrel 41 

" >;iagara Falls,* 47, 48 

■' Section of.* 465 

" Three-Run,* 43, 44 

" Two-Run,* 42, 45 

" Stones, What they are to he, . . 9 

" Altering, 483 

" Burr and Roller 41 

" Brown on Altering, .... 483 

" Changing, ••'••■ ^o 

" Seneca Lake 38 

" Wood Burned in, 187 

(See also sub-heads.) 

Mills', Jonathan. Degerminator, *. . 370 
" Reduction Disc, . . . 369, 372 



Millstone Balancing Device,* 
Millstones, Backing up, . 

" Cleaning.. 

" Success of, 

• ' Exhaust for, . 

" Formula for. Ward's, 

'• Glass, 

•■ Jumping of, . 

■■ Making. . 

'■ Materials of, . 
• Points of Suspension. 

■■ Power Required by, 

"" Transparent,. . 

■■ Ventilation of. 
Mineral Impurities in Feed-Wate 

•■ Oils in Cylinders, . 

" Wool Lagging for Steaui Engines. 
Minnetonka Mill, Fuel Consumed, 
Miscellaneous Chapter, . 
Mitre Friction Pulleys, , 
Mitre, SoUd,* 

" Wheel 

Mixing Wheat. .... 
Model MiU, OUver Evans, Plan of, 
Modem Milling, Progress of. 
Moistiu-e of Belts, .... 

of Fuel 

Molasses for Scaling Boilers, 
MoUne, Water-power of, 
Moore's Diamond Dresser Patent. 
Mortar, 

" for Cellar Walls, . 

■' for Outside Joints, 

■' Freezing of 

" How to Improve. . 

" Sand Requisite for. 

" Mixed with Hydraulic Lime 
Mortise and Tenon,* 
Mortise for Driver, 
Mortise Teeth. Laying out, . 

Mortises 

Motion, Irregular, in Cotton Factories and 
Paper Mills, 

" Irregular, of Electric Light, 

" Unequal Valve, 

" Indicator, to Detect Backlash 
Moulded Cast Gears, 
Mounted Section of Burr,* . 
Mounting of Burrs, Chapter on, . 
Months in which Mills Burn. 

Moving Load, 

Mucedin 

Muddy Feed-Water. 

Mudsills 

Mule Pulleys 

Minden Stone, 

Munson's Geared Under-Runner.* 
Muskrats in Turbines. . 
Musty Grain, to Make Sweet, 
Mutterkom, 



PAGE. 

09, 311 
318 




"\T ARROW Belts, . 

J_N Natural Drought, . 

Nature of Steam, . 

Neatsfoot Oil, Action on Meials. 

Necks of Boilers, 

New Circle Dress,* . 

New Process Burr Mill, . 

Ten-Run Mill. . 
" •' Thousand-Barrel Mill, 
" " Wheat Grinding, Dre>s for. 

New Stock Burrs, 

Furrows for. 
New Style Equalizing Dress, . 
Newton Machine Tool Works, Experimen 
at. Concerning Boiler and Pipe Cover 

tngs, 

New York Belting and Packing Co 
Belt Tests,* . 
Hose, 

Piston-Rod Packing, 
Water-Wheel, 
Niagara Falls Mill,* 

" " Elevator of, . 

'• " Line of Stones,* . 

" " Packers,* 

" Sectional End View,* 

" Turbines of, . 

V\ heel Pit, 



353 

319 

335 

341 

284 

96 

293 

288 

305 

380 

321 

.%1 

147 

148 

165 

187 

521 

235 

224 

224 

525 

69 

379 

200 

117 

153 

75 

355 

17, 21 

17 

17 

14 

!7 

17 

17 

496 

301 

222 

505 

178 
178 
177 
251 
220 



295 

31 

10 

509 

147, 149 

99 

215 

288 

374 

96 

254 

519 



200, 



46, 



288, 



201 

131 

157 

248 

125 

329 

42 

42 

50 

342 

289 

3J4 

o37 



146 



47, 



J 73 
35 

173 
79 
48 
50 
53 
5;3 
49 
47 
5:j 



XIV 



INDEX. 



PAGE. 

Niagara Falls Mill. Wheels, Sid.,* . . 58 

"Nigger Shin" Plane, 487 

Night Hands 521 

Nitrogen 114 

Nitrogenous Bodies 509 

Nolan, Jno. D 513 

Non-Cakiiitf Coal 116 

Non-Condensing Engines 101 

Improved. . 178 
Nordykei Mannon's Plan of Mill Office,* . 70 
Northwestern Roller Mill. Power Required, 76 
Novelty Iron Works Milling Diagram,* 71 
Noye >C Sons' Plan of Deseronto Mills, CI 
•• Two-Run Burr Mill, . 07 
•' Stevens Rolls, . . . 394—400 
Number of Bricks, per Cubic Yard of Brick- 
work. 17 

Number of Bricks Required for Walls, . 16, 17 

" Roll Corrugations, . . . 395 

■• Furrows 324 

•' Quarters 323 

'• Short Furrows, .... Sii 



OAK BARK for Scaling Boilers, . . 1.53 

Oak-Tanned Belts 200 

Oak- Wood 116 

Oat Smut 518 

Oats, Burr for 288 

" Kiln Floors for 264 

" Screens for 264 

" To take out. from Wheat. . . . 2.^5 

Office,* 70 

Oils, Action on Metals of Almond. Castor, 

Linseed and Olive -49 

" Action of Colza. Lard. Neatsfoot and 

Sperm, 248 

Oil in Wheat 510 

" Danger from Fire by 31 

" forSmutter 247 

Oiling Belts 201 

•• Coupling Boxes of Shafting, . . 194 

" Mill Spindles 317 

'• Rubber Belts, 200 

Oils, Compounded and Dangerous, . 247 

" Evaporation of, .... 248 

■■ for Paints 28 

'• Tests of 38 

Old Process Wheat Grinding, Dress for. . 342 

Old Stock 289 

Old Style Equalizing Dress 337 

Oliver Evans' Model Mill of 1790,* . . 69 
One Hundred and Fifty-Barrel Roller Jlill, 

Belting System for 384 

One Hundred and Fifty -Barrel Roller Mill, 

Details of, . . . . . •^83 

One Hundred-Barrel Mill, Fuel for, . . 186 
" " " " Consumption of 

Wood for Fuel. . 187 

Open Belts 199 

upon Cone Pulleys, . . . 229 

" Double Mortise and Tenon.* . . 494 

" Single Mortise and Tenon,* . 493 

" Mortise and Tenon at End of Rafter,* 498 

" Penstock,* 103 

'• Stone, Furrows for 322 

Ordering Bails, 30-1 

•• Burrs, . ' 40, 294 

" Engine, 39 

" Gearing, .- 40 

" Machinery 521 

" Pulleys, Siiafting and Spindles, . . 40 
" Turhmes. Directions for, . . .39, 95 

Oregon Wheat 254. 525 

Oscillating Drive 303 

OscillntingUnder-Runner Horizontal Mill. . 285 

•■ Upper-Runner Horizontal Mill, . . 285 

Oscillation of Mills 10 

■■ of Water in Gauges 123 

Outline of Furrows 324 

Outside Joints, Mortar for 17 

Outward Flow Turbines 81 

Over-heating Flour 359 

Over-Pressure, 163 

Overshot v. Turbines,* .... 83, 84, 85 

Overshot Water-Wheel, 77 

" '• Building, . . 504 

Fall for. ... 78 

" " Large,* . '. . 78 

" . Speed of, . .. 78 



Oxide Carbonic. 
Oxidation of Carbon, 



PAGE. 

114 
114 



Pacific Wheat. . .... 523 

Packers in Niagara Falls Mill.* . . 53 

Packers. Simjison & Gault, .... 477 

Packing. Asbestos 171 

• Bad 177 

" India-Rubber 171 

" Katzenstein Piston-Rod Packing. 171. 172 
" Metal Rings for Engine. ... 17! 
" New York Belting & Packing Com- 
pany's, for Piston Rod. . . . 173 

" Paper, 171 

" Piston-Head 171 

Rod 171 

" Rubber Coil 173 

" Soapstone for 171 

" Tin Foil, .171 

" Webbing for, 171 

'• Wheelock's. for Piston. ... 182 

" Wire-Cloth for Engine, ... 171 

'• Flour in Barrels 476 

Painting 351 

Paints 28 

•' Oils for 28 

Paint Staff, Iron, 348 

Wooden 348 

Pair-Rolls, Running in Opposite Directions, 389 

Pallet's Dress, . ' 342 

Paper Barrels 476 

•• Flour Sacks, Arkell & Smiths', . . 477 

'-' Mills. Irregular Jlotion in, . . . 178 

'• Packing 171 

" Tarred 21 

Paraffine Oil as Lubricant, . . . 246 

ParaUel Flow Turbines 81 

" Furrows, Number of, .... 323 

Part Gate 86 

Partitions, Fire-Brick 30 

■' Hollow Brick, 17 

Pasting up of Bolts, 361 

Patent Handle. (See Picks.) 

Patents, Stevens' 394, et seq. 

Path of the Material in Under-Runner.-, . 321 

" " in Upper-Runners, . 320 

Pearl Barley Machines, Screens for, . 264 

Peat, 115, 116 

Penchet, Cost of Water-Power, at . . 75 

Peninsula Stone 285 

Pennsylvania and New Jersey Dress, . 337 

Penstock 99 

•' Decked.* 101 

" Iron.* 90 

■■ Open.* 103 

" Raised,* 100, 102 

'■ Stone Piers for, 102 

•■ Upright 104 

Percentage of Products in Roller Mid- 
dlings .381 

Perforated Screens,* .... 260—264 

Performance of Steam, .... 159 

" of Steam Engine, n7 

Perg Stone 288 

Persian Insect Powder, 520 

Petroleum for Scaling Oils, ... l-''3 

Phosphor Bronze 193 

for Bearings, . . 249 

Phosphoric Acid in Wheat, . . . 511 

Pick Burr Dresser,* 354 

Picking Rings.* 171. 182 

Picks, :M5 

• for Cracking. 345 

'■ Eyeless, 346 

" Handles for 347 

■' Higgins" 346 

'■ in Patent Handle,* . . . . 34 r 

" Restoring 345 

" Steel for 345. 346 

•' to Grind 316 

'■ to Temper 345 

■ with Eyes.* 346 

Picking and Staffing 344 

Pillars. Cast-iron 14 

■ Settling of, 14 

■ Strength of Wooden. .... 19 

Pine 116 

Pinion Jack, 296 

Pipe Covering, . 145 



INDEX. 



XV 



PAGE. 

Pipe, Drj-,* 128. 139 

Pipes. Feed 143 

'■ Fixed Water. ..'.... 37 

" Steam, 138 

Piston Head, 169. 18-2 

" " Packing for. . . . . 171 

" " Section of.* .... 182 

Piston Rod 169 

'• ■" Packing for, .... 171 

Piston. Leaky 171 

Piston Packing, Wheelock, .... 182 

Pit Wagon Scale,* 472 

Pitch Circles 225 

Pitch of Roof 24 

Pivot Box for Shafting,* . . . 193, 193 

Plain Milling 283 

Plans of Elevators, ... 459, 460, 461, 462 
" of Excelsior Mill,* . . . . ■ .54—56 

■■ for Cockle Machines, .... 42 

■■ of Deseronto Mill, 61 

•■ of Flour Mih 19 

•■ Floor 19 

Plans, Mill,* . 41, 73 

" Circumstances which Determine, 9 

" What to be 9 

Plan of Mill Office, Nordyke & Marmon's,* 70 

" of Ohver Evans' Model Mill, . . 69 

Plans, Preliminary,* 72 

Plan for Rolling Screens 42 

" of Seven-Run Burr Mill (^Richmond 

Works) 07 

" of T-n-o-RimMill,* 46 

" of Yager Mill 58 

Plane Breast and Single Roll,* . - . 387 

Planes, 487 

Plastering, 21 

" Hair for, 22 

" Laths for 22 

Plasterer, Days Work of, ... . 22 

Plaster-of-Paris for Burr Backs, . . . 318 

" " as a Fireproof Material, 29 

Plate Boxes,* 193 

'■ Coupling,* . . . . . 195 

" Gudgeon,* . . . 196 

Plates, Deflecting, for Boilers. . 138 

Plumbago as a Lubricant, .... 245 

" in Steam CyUnders 176 

Point of Suspension of a Burr, . , . 305 
" '■ Sergeant's Method of 

Getting, . . 313 

Poole & Hunt, Gearing, 220 

Pulleys, 229 

Poplar 116 

Porcelain. Discs of, 283 

RoUs 390 

Porous Stone. Furrows for. .... 324 

Porphyry Burrs 288 

Po-ition in Burr Dressing 347 

Position of Belt. Influence of, . . . 199 

•' of Flumes 100 

Posts, Mill 19 

Potash in Wheat 511 

Potatoes for Scaling Boilers, . . 153 

Pounding 175 

Pop Safety Valve. Scovell.* .... 140 

Portable Mills, Spindle for,* .... 376 

Power 75 

■" Carrying Around a Comer by Belt. . 212 

'• Consumption of by Tenants. . 177 

' to Drive Stones 325 

■• How to Order Wheel for, ... 39 

•" Irregular 199 

•■ Loss of. through Gears. . . 220 

■' per Barrel of Flour 76 

■' Required by Christy Brothers & Co., 7ri 

'■ Required for Croweu Roller Mill. 76 

by Blillstones. . . . 3e0 

by Roller Mills, . . 380 

for Northwestern Roller 

Mill. . ... 76 

for Standard Mill. . 76 

for Washburn B & C JliU. . 76 

■" Steam Ill 

'■ Variations of 96 

■■ Waste of 75 

'■ Waste of. b.v Improper Lubrication, etc., 177 

Precautions against Fire, . . 3:3 
Preliminary Mill Plans,* . 71, 72 

Preparations for Raising Roofs, ... 23 

Pressure of Air, 157 



Pressure of Steam. . 

•• Absolute. 

"■ Atmospheric. . 

■■ Average Total. 
■ Back 

■■ on Bearings. 

" Gauges 

" Initial. Required. . 

" Mean Effective, 

" Over 

" Total Initial, . 

■■ Total. Final. . 

■■ '"Lender.'' 
Preventing Scale in Boilers. . 

'• Fire 

Prices of Turbines. . 

■• of Wheat. Tables of. . 
Priming 

■■ caused by Scale. . 

Problems, 

Progress of Modern Milling. 
Processes. Definitions of. 



PAGE. 

159 
163 

161 
159, 181 
101, 184 

250 



141 



155 
184 
162 
163 
159 
159 
163 
152 
29 
91 
527 
126 
148 
537 
377 
380 



and Systems .37' 



Pron.y Brake, 

Proof Staff. Circular Iron* .... 

Case for.* 

Proportions of Bearings 

■ of Building 

■■ of Boiler Setting 

Proportion of Land to Furrows. . 

■ of Boilers 

" of Mortar in Brick-Work. . 

Protection from Fire 

'■ from Lightning 

Pulleys 

"' Beveled Friction,* .... 

■ for Burrs. 

■• Calculations, 

•■ Cement for Leather Covers. 

" Cast-iron. 

• Covering, 

■ Centres of. Distance between, . 
■ ■ Driving Power of. .... 

■ Diameter. Influence of, . . 

■■ Flat Belts for. 

■■ Friction,* 

■ How to Order, 

■■ Idle. ..... . . 

■ Influence of Revolutions per .Minute. 
Pulley. Influence of Crown 

" "influence Exerted by Condition of. . 

Pulleys. Lagging 

•■ Leather, Lagging for. ... 
■• Loose 

• Mitre Friction, 
•■ Mule,* 

■ Poole & Hunt's. Baltimore. 

■ Rankin's Rule for Stepped. 
■■ Right Form of Beveled Friction,* 
" and Shafting. Set-Screws for. . 

■ Size of 

• ■■ Slipping 

; ■■ Speed of 

■■ Split 

■ Stepped . . 

" Tightening for Belts, 

" Transmission by 

■ Tractive Force of Friction. 

■ Weight of 

I ■• Wrong Form of Beveled Friction,* . 

" Wrought-Iron Rim 

j Punching Screens 

1 Pure Water. Effects of, in Boilers. 

! Purifiers 

Air Current for 

Capacit}- of 

Centrifugal 

Cleaning Cloths 

Clothing for. 408. 416. 

on Coarse Middlings. . . 410, 

Cost and Depreciation of. . 

for Custom Mills. ... 

Electrical 

Function of 

for Germ Middlings 

G. T. Smith's Patents.* 

for High Grinding. 

Keeping Cloths Clean. 

for .Merchant Jlills. 

for New Process. . 



17 
349 
349 
250 
iO 
137 
322 
125 
17 
34 
25 
■229 
235 
296 
537 
235 
202 
235 
199 
2;i5 
199 
229 
235 
40 
233 
199 
199 
199 
234 
2:35 
2:33 
235 
215 
229 
230 
235 
199 
201 
234 
201 
230 
2-,'9 
203 
229 
234 
229 
235 
202 
257 
150 
41 
41S 
417 
409 
416 
421 
411 
522 
421 
409 
409 
l20 
414. 415 
422 
412 
421 
422 



202, 



XVI 



INDEX. 



Purifiers, Ordering . 

" Original in Washburn Mill, 

" for Old Process, 

" Prices of, . 

" Returning on, . 

" Principle of, . 

" for Spring Wheat, . 

'■ (Look under Middlings 
Wheat Meal Purifiers 
Purification, Trouble with 
Purity of Lubricants, 
Putting on Belts, 
Pyrethrum Eoseum, 

Pumps 

Pump. Rotary, . 

" Where to put Feed, 
Pumping Hot Water, 



292, 



QUALITIES of Burrs, 
Qualities of Fuel, . 
Qualities of Wheat, 
Quantity of Bread from Flour, 

" of Dirt in Wheat. . 
Quarry, Esopus Stone,* . 
Quarter Dress. . 

'■ Wrong Arrangement 
Short Furrows in. ' 
•' " Straigiit,* 

■' Sickle,* . 
" Common,* 
Quarters, Number of, 
Quarter-twist Belt,* . 209, 211, 212, 213, 



342. 



PAGE. 
424 
416 
422 
417 
418 
409 
422 



Purifiers and 

) 



359 
248 
206 
520 
34 
34 
143 
143 



of 



RACE. Tail 
Rack for Flumes, . 
Radiation from Furnace, 
Radiators, Cast-iron, 
Radius of Furrows, 

" of Gyration 

Rafters.* 

" for Sloped Roof, . 

Raised Penstock 

Ram. Hydraulic 

■ • Capacity of , . 
Rankine's Rule for Stepped Pulleys, 
Rate of Combustion, 
Rates. Expansion, .... 

Rating of Engine 

Rats. 



to Prevent Gnawing Leather Belts, . 

Rawhide Belts 

Reaction Water Wheels. . . . . 
Rectangular Boilers, . . . . . 

Rectilinear Furrows, 

Red Heart Hickory, 

Red Oak 

Redressing 

Red Staff 

Red Staff (see Paint Staff). 

Reduction Disc Mills',* 

" Machine Mills',* 

Red Winter Mediterranean Wheat, . ■ . 
Reels for Ending,* . . . . . 

Reel Jack for,* 

Reels, Cost and Depreciation of, . 

" Explosion of, 

" for Breaks.* 

" for Coarse Dirt,* 

" for Coarse Tailings,* .... 

" for Ended Wheat,* . . . . 

" for Fine Tailings, 

" for Large Wheat.* . - . . 

" for Light Material,* . . . . 

" for Middlings,* 

" for Small Semolina,* . . . . 

" for Straw. Dirt, &c.,* . . . . 

" for Tailings 

" for Wheat.* 

Reflectors. . . . ■ . . 

Register Gate.* 

Regnault's Experiments Concerning Tem- 
perature of Steam 

Regrinding. Dressing for, .... 

Regular Expansion, 

Regular Single Jlortise and Tenon,* . 

Regulator for Draft, 

Regularity of Speed of Steam Engine, 
Relative Admission .Periods of Steam, 



117 
523 
525 

254 
293 
337 



328 
336 
336 
341 
323 
214 



94 
106 
115 

37 
333 
309 
498 

22 
102 

35 

36 
230 
116 
184 
177 
520 
204 
200 

81 
121 
324 
117 
117 
352 
348 

372 
369 
525 
257 
434 
522 

33 
443 
443 
444 
265 
444 
263 
444 
266 
266 
265 
374 
443 

38 



158 
341 
159 
496 
142 
165 
159 



PAGE. 

Relative Cost of Water and Steam Power. '5 

Release 177 

Removing Scale in Boilers, .... 153 

Repairing Boilers 125 

Restoring Picks, 346 

Return Tubular Boiler, 127 

Reversed Furrows 323 

Revolutions per Minute of Pulley. Influ- 
ence of, 199 

Rhinestone 28rf 

Rice's Steam Generator for Heaters,* . 2(S0 

Rice Wrevil, 519 

Richmond City MUl Works Burr Crane. 317 
Belt Tightener, 203 
" " " Plan of Seven- 
Run Mill, 67 

Righter Boiler 122 

Rigid Runner Horizontal Mill, . . 288 

Rim Speed of Burrs, 358 

Rings in Burr Faces, . . . . - 295 

Rings, Packing,* 171, 182 

Rittenhausen, Analysis of Gluten, . 509 

Rod. Piston, 169 

Roll Pairs 388 

• Pair, Running in Opposite Directions,* 389 

Roller and Burr Mills 41 

Roller Frames, Belts for 389 

Details of, ... . ;386 

" '■ Gears for, .... 389 

■' Frame. Gray's,* 402 

" Machines, 'Varieties of, ... 386 

'■ Milling. Percentage of Products in. . 381 

" Mill, First, 382 

'■ Shafting for 450-bbl 42 

•' " Smallest that will Pay to Put up, 42 

■' Mills. Power Required by. . , . 380 

■■ Milling. Building for, . . . . 41 

Rollers 482 

Roller. System, Hungarian, .... 380 

Rolling Friction 243 

" Screens, 257 

Plan for 42 

RoUs, I iseuit 390 

•' Bran, 482 

■' Chilled Cast-iron 390 

" Coefficient of. Friction from, . . 391 

" Conical 284 

" Cylindrical 286 

" Diameter of, 389 

" ■ Differentially Speeded Saw Tooth,* . 392 

" Equally Speeded Saw Tooth,* . . 393 

" for Bran 395 

" for Cockle 266 

" for Hard Spring Wheat, . . . 395 

" for Soft Winter Wheat, ... 395 

" Friction, Drive for 286 

" Germ, 482 

" Grooved Chilled-Iron 287 

" Hyperboloid, 284 

" Length of 389 

" Link Belt, Drive for 286 

" Materials of 286, 390 

" Methods of Driving, . . 3^6, 388 

" on Soft Wheats, 394 

" Porcelain, 390 

" Saw Tooth, 392 

" Scotch 394 

" Single 386 

" " Acting against Curved Face, . 286 

Cost of Making Flour by, . 523 

" Smooth 482 

Chilled-Iron 287 

Porcelam Biscuit, . ... 287 

•• Soft-Iron 390 

" Stevens 389 

" Surface of 286, 390 

" Three High, 286, 386 

" Toothed,* 394 

■' Whiteness of Flour from, ... 391 

Roofs 22 

" Danger to, by Fire, .... 23 

" Height of 22 

" for Snow, 23 

" Iron, 23 

" Mansard, 30 

" Pitch of 24 

" Preparations for Raising, ... 23 
" Protection against Lightning by 

Metal 26 

" Sheathing, 23 





INDEX. 


xvii 




PAGE. 




PAGE 


Roofs, Sloped 


22 


Screeching of Belts, 


203 


" Tin, 


23 


Screens, 


278 


Room, Steam, 


127 


" for Various Materials, . 256 


. 257. 262—264 


Rope, Deflection of Wire, 


239 


" Harrington & Oglesby's Graded. . 264 


" Distance of Transmission by Wire 


2;37 


■• Punching 


257 


" Driving, . . , . 


239 


" Perforated, .... 


259 


'■ Duration of Wire, .... 


239 


'■ Rolling 


257 


• Horse-Power of, . 


237 


'' Plan for Rolling, 


42 


" Sheave for, 


2S9 


" Shaking 


257 


■' Tension of Wire, .... 


237 


" Sheet Metal,* . . 26( 


), 261, 262, 263 


'' Transmission, .... 


237 


■• Wire,* 


258 


•' Wire, 


199 


Screw-Bolt Feeder,* 


435 


Rotary Pumps, 


34 


Screw-Drivers, 


487 


Round Corrugations 


390 


Screw, Lighter,* .... 


316 


Rubber Belt 


200 


Scubbing Burrs, 


257 


" Belts, Linseed Oil for, . 


204 


Seal-Oil, Action on Metals, . 


249 


" " Slipping of, . . . 


204 


Seamless Cotton Sacks, . 


4:6 




309 


Seamless Steam Boilers, 


131 


Coil Packing 

" Stamps, Holderness & Co., 


173 


Seams of Belts, .... 


206 


481 


Secole Cornutum, .... 


519 


Rubbing Burrs 


353 


Secondaries, Number of. 


323 


Rules for Management of Steam Boilers 


, . 154 


Sectional Koiler Covers, 


146 


Running Away of Engine, 


167 


" Boilers, 


119 


Running Balance, .... 


307— iog 


" Plaster Boiler Covering, 


146 


Brown's Method of G 


et- 


•■ View of Niagara Falls Mill a 


ad Ele- 


ting, . 


312 


vator,* .... 


. 49. 51 


Running, Cheek on Engine, . 


177 


Section of Burr,* . . . aOf 


, 303, 321. 373 


Russian Wheat, 


511, 525 


" of Mill,* 


465 


Rust, 


518 


" of Piston Head,* . 


182 


Rye Grinding, Dress for Lower Kuni 


ler 


Seed Coats of Wheat Berry, . 


513 


for, 


339, 340 


Seeds, Sieves for, .... 


273 


Rye Grinding, Dress for, 


342 


Self-Oiling Journal Boxes for Shafti 


ng, . 192 


" " Middlings, 


422 


■■ Post Journal Box,* 


193 


Stone for. 


288, 289 


Semi-Bituminous Coal, . 


117 


" Screens for, 


264 


Semi-Tanned Belts, .... 


200 


" When to Clean 


256 


Seneca Lake Mills 


38 






Sensible Heat of Steam, . 


157 






Separating Machine. Capacity of. 


256 


QACKS, 

O Sacks, Jute, 


476 


Separation. . . : . . 


264 


476 


Separator,* 


274 


Sacks. Paper 


477 


" Cockle Manufacturing Compa 


ny. 267 


" Seamless Cotton, .... 


476 


" Grader & Dustless, 


273 


Saws 


487 


■■ Place for 


. . 256 


Safety Valve, 


139, 155 


'■ Richardson's Oat, . 


267 


" Area of 


141 


■■ Lubricants for. 


245 


" Danger of Overloading, . 


141 


" Screens for, .... 


264 


" " Duplex, .... 


141 


(Look also tmder "Cockle 


" and 


" ScovellPop, . 


140 


'•Oats,") 




Sagging of Beams 


19 


Sergeant, W. E., Method of Getting 


' Point 


of Mill 


19 


of Suspension, . 


313 


of Belts 


202 


Set-Screws for Shafting and Pulleys 


198 


Saint Blasieu Turbine, .... 


95 


Setting Driver-Boxes, 


303 


Saltillo Turbine, 


95 


" Hopper Bevels,* . 


500 


Salt in Feed-Water 


147 


" of Boilers, .... 


122, 134 


Sand in Feed-Water. - « ■ 
•■ Requiste for Mortar, 


148 


■■ the Bed, . . . • . 


297 


17 


■' Turbines, 


99 


Sandstone Burrs, . . 


288 


Settling of Building, 


10 


Sardinian Burr, ... 


288 


" of Pillars 


14 


Sarospataker Burr, .... 


288 


Seven-Run Burr MUl, Richmond 


Works 


Sashes, Iron, ... . . 


38 


Plan of* 


. 67, 68 


Saving by Using Steam Expansively, 


161 


Shaft, Scarf -Spliced,* 


195 


Sawdust. Burning 


132 


Shafting, 


188 


•' in Turbines, 


96 


" Barfting, .... 


190 


Saw-Tooth Rolls, .... 


392 


" Buying 


190 


" '■ Equally Speeded, 


393 


'• Calipering, .... 


189 


"S" Burr Blocks, .... 


289 


■" Clutch for Line, 


196 


Scale, in Boilers, ... 


125 


- Cold-Rolled, .... 


190 


" caused by Animal Oil in Cylinders 


175 


'■ Columns for, .... 


19 


" causing Grit in Steam Chest, 


148 


■■ Couplings, 


189, 193 


" Foaming caused by, . 


148 


" Cresson's, .... 


188 


" Loss of Heat by, .... 


148 


■■ Diameters of, .... 


188 


" Priming caused by, 


148 


■' Directions 


40 


" Stoppages caused by, . 


148 


■■ Fly- Wheel upon. . 


194 


•' Dormant,* 


470 


•■ for 450-bbl. Roller Mill, 


42 


•• for High Pressure Steam Engine,* 


162 


■ Hangers for 


191 


Scales, Hopper,* . ... 


471 


■■ Hollow 


191 


Scaling Boilers 


125, 151 


■■ Hot-Rolled, .... 


190 


Scalping Reels. Where to go. 


42 


■■ Improper Alignment, . 


177 


Scarf -Spliced Shaft,* .... 


194, 195 


• Journal Boxes for. 


192. 193 


Schleider, ....... 


510 


■• Keys for 


198 


Schmidt on Furrow-Crossing, 


331 


•' Key Seats in 


193 


ScovellPop Safety Valve,* . 


140 


•' Line Couphng, 


194 


Scouring 


295 


" Lining up 


198 


■" Machines, 


256 


" Oiling Coupling-Boxes, 


194 


" Screens for 


264 


" Scarf-Splice for. . 


194 


(See also Smutters), 




" Self-Oiling Boxes for, . 


192 


Seranton Coal 


116 


" Sizes of, 


188 


Scraping Slide-Valve Seats, . 


174 


" Speed of 


191 


Scratch Coat, 


21 


" Springing of 


19l. 192 


■^ Roll. 


394 


" Torsion of, ... 


193 



XVIU 



INDEX. 



PAGE. 

188 
188 
188 
202 
522 
257 
394 
133 
117 
77 
121 
353 
392 
332 
21 
21 
23 
237 
260, 461, 462, 463 
117 
121 
3(24 
224 
215 
815 
20 
323 
225 
326, 336, 337 
252, 257 
255 
475 
273 
273 
273 
273 
273 
273 
273 
273 
315 
511 



Cleaning Ma- 



Shafting, Turned, . 

" Wooden, ... 

" Wrought-Iron, 
Shafts, Distances of, 

" Straightening Crooked 
Shaking Screens. 
Shallow Corrugations. . 

" Grate Bars, 
Shaly Coal, 
Shape of Floats, 

" of Boilers, 
Sharpening Furrows, 
Sharpness of Corrugations, 
Shearing Action of Furrows, 
Sheathing, Diagonal, 

" Frame Buildings, 

" Roofs. 
Sheave for Wire Rope,* 
Sheet-Metal Screens,* 
Shell-bark Hickory, 
Shells, Boiler. . 
Shell-Wheels,* . 

" " Bevel and Spur, 
Shifter for Belts. . 

" for Fast-Running Machinery, 
Shutters, Corrugated Iron, 
Short Furrows, Number of, 
Shoulders of Gear Teeth, 
Sickle Dress,* , 
Side-Pull upon Spindles, 
Sieves 

" Testing. . 

" for Barley, 

" for Cockle, 

" for Corn Screens, . 

" for Flox, . 

" for Grain Cleaning, 

" for Oats, . 

" for Receiving Riddles, 

" Perforations for, . 
Silent Feed.* . 
Silica in Wheat, 
Simpson & Gault Mfg. Co.'s 
chines, 

" Packers,* 

" Grain Metres, . 
Single Cylinder Cockle Machine,* 
Single Leather Belts, 

'■ Link Conveyor,* 

" Roll against Concave or Plane Breas 

" Roll Acting against Curved Face, 

" Rolls 

" " Cost of Making Flour by, . 

" Roller Frame, Jones',* 

" " Mills, Jones, Ballard & Ballard 
Site, MiU, to choose. 
Size and Weight of Stone 
Size of Burr Blocks, 

" of Engines, 

" of Pulleys, 

" of Shafting, . 
Six-Reel Chest.* 
Skylights, . 
Slack Belts, 
Slat Conveyor,* 
Slicing Fires, . 
Slides of Steam Engines, 
Slide-Valve and Automatic Engine Com 
pared. . . ' . 

" " Engine, Cut-off. 

" " Fitting to its Seat, 
Sliding Friction, . . . . 

Slip of Belts 177, 202. 

Slippery Elm for Scaling Boilers, 
Slipping Pulleys, 

" of Rubber Belts, . . . 

Sloped Roof 

Slow Combustion, 

Smallest Roller Mill that it will Pay to Put 

up 

Small Semolina, Reels for,* . 

Smith, Geo. T., Purifier, Sectional View.* 

Smoke Connections, .... 
" Consumer, McGinniss', ' 
" Prevention by Draft Regulator, . 

Smooth Chilled-Iron Rolls, . 

Smoothness of Lands and Furrows, . 

Smooth Porcelain Biscuit Rolls, . 

" Rolls, ... , . . 386, 
" " Action of,* .... 



314, 



256 

477 
473 
268 
201 
217 
387 
286 
386 
523 



s, 387 



201. 



203, 



136. 



390, 



296 
288 
175 
296 
188 
440 
24 
202 
217 
118 
169 

186 
174 
174 
243 
204 
153 
334 
200 
22 
32 

42 

2fi6 
415 
126 
137 
142 
287 
336 
287 
482 
390 



322, 



336, 



Smooth Rolls, Differential Speed of, 

" '• Power Required for, 

" " Regrinding with. 
Smut, 

" Machines, 
Smutter,* 

" Cost and Depreciation of, 

•' Oil for 

" and Separator, Champion, 

" Screens for, . 

" and Separator, Setting up, 
Smutters, Lubricant for, 
Snows, Roofs for, . 
Soapstone for Packing, . 
Soda Ash for Scaling Boilers. 

" in Feed-Water, 
, " in Wheat, 
Sodium Chloride in Vrheat, . 
Soft Coal, Danger from Fire, 

" Deposits in Boilers, 

" Iron Rolls, 

" Metal Bearings, 

" Wheat, .... 

" " Furrows for, 

" " Grinding, . 

" " Rolls on, 

" Winter Wheat, Rolls for, 

•' Wood 

Softness of Wheats, 

Southern Wheat, 

Solid Friction, .... 

" Gear- Wheels, . 

" Spur 

Soot causing Corrosion of Boilers, 

" in Boilers, ... 
Sounding for Wheel-Pit, 
Southern Pine, .... 
Space, Steam, . . , . 

" Water 

Specky Flour 

Speed of Belts 

" " Influence of, . 

" of Elevators, , 

" of Engines. 

" of Gears and Pulleys, . 

" of Grinding, . 

" of Overshot Wheel, 

•' of Pulleys, 

" of Shafting, . 

'• of Steam Engines, . 

" of Wheat Burrs, . 
Sperm Oil, Action of, on Metals, 

'■ " as Lubricant, 
Spheres, Calculations, . 
Spindle,* 

•' Coil Spring for, 

" Expansion of. 

" for Portable Mills,* 

'■ Lubricant for, 
Spindles. How to Order,. 

" Side-Pull upon. 
Spiral Clutch, 

" Coupler, 

" Furrow, 
Splice of Belts, 
Splint Coal, 

Split Pulleys, Cordial upon. 
Splitting and Degermination, Ideal,* 
Spontaneous Combustion, 
Spreading Device and Adjustments,* 
Springing of Shafting, . 

" of Walls, to Prevent, 
Spring Wheat, American, Analysi 

" " " Bolting, 

" " " Dress for. 

'• " " Purifier on 

" " to take Oats from. 

Sprockets for Detachable Link Chains, 

Spruce, Pine 

Spur Shell Wheels,* 

" Wheels, Cost and Depreciation 
" Solid,* 
Square Feet of Heating Surface for Mills, 

" Inches of Water, 
Squares, 

Stable Equilibrium,* 
Staff. Circular Iron, 

" Red, . 

" Wooden Red,* 
Staffing,* . 



is of, 



of. 



PAGE. 

V96 
.391 
391 
518 
257 
275 
523 
247 
274 
264 
276 
345 
23 
171 
153 
147 
511 
511 
33 
152 
390 
250 
381 
332 
360 
394 
395 
116 

523, 381 
525 
243 
224 
224 
150 
153 
13 
117 
126 
125 

432, 436 
201 
199 
219 
175 
538 
359 
78 
201 
191 

164, 165 
482 
248 

245, 246 
537 

296, 298 
251 
359 
376 
245 
40 
352 
195 
195 
325 
205 
117 
2.30 
372 
248 
404 
192 
13 
511 
437 
342 
422 
256 
219 
117 
224 
522 
224 
37 
91 
487 
307 
349 
348 
348 
348 



537, 



INDEX. 



XIX 



of, 



Feed 



Staffing and Picking, 

Stamps, Rubber, Holderness & Co., 

Standard Mill, Power Required 

Standing Balance,* . 

Starch in Wheat, 

" for Sealing Boilers, 
(See also Amidon.) 
Staying of Boilers, . 
Steam Domes,* 

" Generator for Wheat Heaters,* 
Steam, 

" Chest, .... 

" Coils 

" Cylinders, Graphite in. 
Lagging. 

" Material for, 

" " Vacuum in. 

Steam Domes, Le Van on, 

" " Weakening Effects 

Steam-Drum, . 
Steam, Dry, 

" Economy of, . 

' ' Expansion of, 

" High Pressure, 

" Mechanical Effect of, 

" Nature of, 

" Performance of, 

" Pressure of, . 

" Relative Admission Periods, 

" Saving by Using Expansively, 

" Superheated, .... 

" Throttling, .... 

" Using Exhaust for Heating 
Water, 

" Wet, 

" Wire-Drawing, 
Steam-Jacket Heater and Purifier, 

Steam-Pipes, 

Steam-Pipes for Fire Extinguishment 
Steam-Ports, Area of, 
Steam-Power, Cost of Putting in 

" " V. Water-Power, 

'" Pressure, Mean Effective, 

" Room, .... 

" Space, .... 

■■ Traps 

Steam Engine, .... 

" Back Pressure in, 

" " Clearance in, . 

" " Compression in, 

" '■ Condition of, . 

" " Corliss Type of Valve for, 

" " Cost of 50 Horse-Power, 

" " Cost of 100 Horse-Power, 

" " Cushioning, 

" " Economy of, . 

" " Economy of High Pressure 
in, 

" ■' Foundation for, 

" •' Governor Tests of, 

" " Measure of Economy of 

Shdesof, . 

" " Leveling Bed of, 

" Waste of Power in. 
Steel Boilers, .... 

" Bushes for Steam Engine Cylinders, 

" Connecting Rod, 

" Crank of Engine, 

' ' Hardening, 

" for Picks. 

" in Wheat. 

" Stepped Pulleys, 
Steps, Lignumvitffi, 
Steps of Turbines, 
Stevens' Patents, 

" Rolls, 
Stencils. 

Step, Drop-Lift,* 
Stepped or Cone Pulleys,* 
Stiff V. Oscillating Drive, 
Stiffening of Single Leather 1 
Stiffness of Journals, 
Stones, Capacity of, 

" Choice of. 

" Dressing, 

'■ for Middlings, 

" for Rye, . 

" for Ending, . 

" for Hulling, . 

" Line of, in Niagara Falls' Mill,* 



30' 



125, 



149, 



Brits, 



157, 



165, 



a45. 



25T. 



PAGE. 
344 
481 
76 

■, 308 
510 
153 

128 
129 
280 
114 
169 
37 
176 
165 
168 
161 
138 
128 
128 
138 
185 
158 
126 
157 
157 
159 
159 
159 
161 
164 
161 

147 
164 
161 
164 
138 

37 
169 
185 

75 
183 
127 
126 
145 
177 
162 
164 
163 
177 
161 
185 
185 
163 
177 

162 

167 
167 
162 
169 
167 
177 
119 
168 
170 
170 
345 
346 
254 
229 

95 

95 
394 
389 
481 
434 
2.30 
303 
201 
250 
322 
521 

15 
289 
289 
266 
288 

53 



PAGE. 

Stones for Wheat, 288, 289 

" Granite 288 

" Uneven Wear of, 3:^5 

Stone-Lift, Automatic 316 

Stone Piers for Penstock 102 

" Walls, Cost of 15 

Stoppages caused by Scale, .... 148 

Stop-Valves 127, 139 

Storage, Floors for, .... 20, 481 

" House, 10 

" of Flour, 476 

Straps, Heating of Eccentric, ... 173 

" Eccentric 173 

Straight Quarter Dress,* . . . 325, 336 

Straightening Crooked Shafts, . . 522 

Strainer 143 

Straw, Dirt, etc.. Rules for,* . . . 265 

Stream, Measuring Fall and Width of,* 111 

" Power Ill 

Strength of Beams, 18 

■' of Boiler Plates, 120 

'■ of Bricks, 16 

" of Single Leather Belts, ... 201 

Stretching of Belts, .... 203, 204 

" of Detachable Link Chains, . . 219 

Stroke of Engine 169 

Strength of Flour, 476 

Strong Flour, 517 

Stuffing Boxes, 171 

Submerged Orifices, Velocity of Discharge 

of Water through. . ... 93 

Sugar in Wheat, 510 

Sulphate of Lime causing Foaming in 

Boilers 147, 152, 153 

Sulphate of Magnesium in Feed-Water, . 147 

Sulphur for Hot Bearings, .... 244 

Sulphuric Acid in Wheat, .... 511 

Sulphurous Coal causing Boiler Corrosion, 150 

Sumac for Scaling Boilers, . . 153 

Superheated Steam 164 

Superheating Chamber, 139 

Support of Floor Beams 19 

Supposed Path of Material, .... 321 

Surface Grate, 131, 132 

•• of Rolls 286, 390 

Suspension, Methods of Getting,* . . 313 

Sweeping Boilers 126 

System, Jonathan Mills' 303 

'■ Jones 385 

" Hungarian, 382 

" Roller. . 380 

Systems and Processes, 379 



477, 



TABLE for Weirs, 
Table of Urate Areas, Barr's 
Table of Saving by Using Hot Feed-Water, 

" Showing Saving by the Use of High 
Pressures in Steam Engines, 
Taking Out of Wind, 
Taihngs, Reels for,* 

" Rolls for, 

Tail-Race, 

" Area of. . 
Tallow as a Lubricant, . 

Tallies,* 

Tally, Electriq^* 

Tallies, ELarre" 

" W. N. Durant's; . 
Tangential Force,* . 
Tanks. Capacity of, 

" Weight of, . . . 
Tannic Acid for Scaling Boilers, 
Tar for Weevils, 
Tarred Paper for Sheathing, . 

Tegumen 

Teu, Lime of, . 

Temperature of Feed of Boilers, 

" of Fire 

" of Steam, Regnault's Exper 
Tempering Picks, . 
Templet Odontograph, . 
Tendency of the Heavy Side.* 
Ten-Run New Process Mill, . 
Tension 

•' of. Belts 

" of Wire Rope, 
Terra-Cotta Arches for Floors, 

Tests, Expert 

Test of Boiler Plates, 



iments 



245, 



478, 



513, 



199, 
202, 



110 
132 
148 

163 
350 
444 
394 

94 
100 
246 
478 
479 
479 
479 
307 

34 
2.34 
153 
520 

21 
516 
120 
143 
117 
158 
345 
221 
310 

42 
244 
205 
237 

20 
177 
119 



XX 



INDEX. 



Emerson. 



Tests of Bricks, 

" of Driving Power of Belts, 
" of Governor, . 

•■ of Oils 

'■ of Steam Engine Governor, 
'■ of Turbines, . 

by Herschel, 
'■ of Water-\Vlieels by James 
" \^^th various Dresses, . 
'■ in Holyoke Flume, 
Testers, Flour,* 
Testing Boiler Plates, 

■" Driving Power of Belts, 

" Sieve 

•' Strength of Belts, . 
Texas Pea, .... 
Thermometer Attachment for 

Heaters Durant's,* . 
Tliickness of Belts. Influence of, 
" of Gear Teeth, 
" of Gear Wheels, . 
" of Mortar Joints, . 

Thin Belts 

Thousand-Barrel New Process Mill, 
Three ffigh Rolls, . 
Throttle, New Form of,* 
Threshing Machines, Screens for. 
Three Hundred-Barrel Mill, Uoal for 
Three-Run Mill,* .... 

Throttle Yalve 

Throttling Steam, .... 
" and Wire-Drawing, loss by. 
Throwing Over in Steam Engines, 
Tightening of Belts, 

•■ Pulleys for Belts, . 
Tightenei-s for Detachable Link Chains, 

Tilleda Stone, 

Tilletia Caries, 

Timber, Green, .... 

'■ Joints.* 

Time to Build, 

Timothy, Screens for. 

Tinfoil Packing, .... 

Tin Roof 

Tin, Quantity to Cover Given Surface 
Toope Boiler Covering,* 

Tools needed, 

Top-Lift Tram-Pots.* 

Torsion of Shafting, 

Total Initial Pressure, 

Total Heat of Combustion. . 

Towne. Horse-Power upon Tractive Force 

of Leather Belts, 
Trachyte Burrs, 

Tractive Force of Leather Belts, 
Total Final Pressure, 
Tram -Pots,* .... 

Trams, 

Tramming and Bridging, 

Transmission 

■' Advantages of Belt, 
" By Chains, 
" by Gearing, . 
'■ Long, .... 
" Wire Ropes, . 
" by Pulleys, 
Transparent Millstones, . 
Transportation, Cost of. 
Trap Doors,- .... 
Traps, Expansion Steam, 
Trier, Flour.* .... 
Troubles in Grinding, 
Trunnions, Main Valve of ^Vheelock En 

gine,* .... 
Tubes. Draught of, . 
•■ Corrosion of, . 
" for Boilers, 
Tubular Boilers, 

" Boilers in Limy Districts, 
Tubulous Boilers. . 

Turbines, 

" Double, .... 
" How to Order, 
■" Compared with Overshot,* 
" Eels and Muskrats in, . 

" Bark in 

" Centre Vent, . 

" Clogging of, . . 

" Dimensiqns of. 

" Discharge of Water from, 



PAGE. 

16 
207 
106 

38 
167 

86 

87 

86 
335 

86 
475 
121 
207 
475 
207 
256 
Wheat 

281, 282 

199. 200 

225 

226 

17 
200 

50 
28S, 386 
182 
264 
187 
42— M 
180 



202. 



301 



161 
161 
169 
177 
203 
219 
288 
518 

19 
491 

14 
264 
171 

23 
23, 24 
146 
487 
302 
193 
159 
115 



233 

288 
233 
159 
301, .302 
487 
297 
11, 188 
199 
216 
220 
239 
237 
229 
320 
525 
23 
145 
475 
359 



122, 



80. 



182 

106 

131 

122 

127 

148 

124 

85 

95 

39 

83 

96 

96 

81 

96 

91 

82 



PAGE. 

Turbines, Draught Tube for, .94 

" Flume for, 92 

" High Heads for 94 

" Inward Flow, 81 

" Leaves in, 96 

" Maximum Velocity for. ... 81 

" of Niagara Falls Mill 48 

" Outward Flow 81 

" Parallel Flow, 81 

'• Prices of 91 

" Rack for, 106 

" atSaltillo 95 

" Sawdust in, 96 

" Setting 99 

" at Sr. Blasieu 95 

" Steps of Lubricating, .... 95 

" Tests of 86 

'• Useful Effect of. . . .86 

" V. Vertical Wheels, 73, 78 

" Victor 87 

•' Water Required by, ... 93 

" Wheels, Ordering, ... 95 

'• Wooden Flumes for, ... 103 

Turned Shafting, 188 

Turpentine in Paint, 28 

" for Bugs in Reels 431 

Twist of Corrugations 395 

Two Hundred and Fifty-Barrel Mill, Fuel 

Consumed 187 

Two Hundred and Fifty Horse-Power Steam 

Engine. Cost of 185 

Two Hundred-Barrel Mill, Fuel Consumed, 186, 137 

Two-Run Burr Mill.* .... 42, 45 

No3-es & Sons, 67 

•' Low Grinding Mill, ... 42 

" Mill, Changing, 481 

Two-Story Boiler, 122 



285, 
s for 

sfor 



UHLINGER Diamond Dresser, Patents 
Unburnt Fuel, Loss by. 
Unconsumed Air, Loss by, 
"Underpressure,". 
Under-Runners, .... 

Lower Stone of Arndt' 
Rye,* . 
" " Lower Stone of Arndt 

Wheat,* 
Path of Material in, 
Undershot Wheel, . . 
Uneven Wear of Stones, 

Units, Heat, 

Unstable EquiUbrium,* . 
Unsteady Water-Power, 
Upper Bed-Stone,* ... 
Upper Runners, Dresses for,* 

Path of Material in. 

Upright Penstock 

Uredo Linearis, .... 
Uredo Rubigo, ... 
Useful Effect of Turbines, . 
Use of Experts, ... 
Using Draft Square,* 
Ustilago Carbo, .... 
" Maydis, 



VACLTUM in Steam Cylinders. 
Value of Lubricant, 
Value of Wood for Heating, 
Valve, Blow-off, 

" Check 

" Gear for Steam Engines, 
type 

" Motion, Uneven, . 

" Rod 

" Safety, 

" Seat, Fitting SUde to. . 

" Seats. Scraping, 

" Left-hand, 

'• Pop, 

" Safety, 

" Stop, 

" Throttle, 

Various Grades of Burr-Stone. . 

" Millstone Dresses (Chap, xxiv., 319), 
Variations of Power, 
Variegated. Burr-Stone, .... 



325 



CorUss 



355 
115 
114 
163 
320 

3.39 

340 
321 

77 
325 
115 
307 

96 
375 
3.30 
320 
104 
518 
S19 

86 
179 
353 
518 
518 



161 
244 
117 
145 
139 

161 
177 
171 
139 
174 
174 

34 
140 
155 
139 
180 
389 
342 

96 
288 



INDEX. 



Varieties of Roller Machines, 
Vegetable Glue 

■■ Grain Destroyers, . 
Velocity and Discharge of Water, 

" through Submerged Orifices, 

" Gauges of, .... 

" of Steam, .... 

■' of Water, .... 

'■ Ratio of Gear Wheels, 
Ventilating Action of Furrows, . 
Ventilation of Buildings, 

■■ of Millstones, 
Vertical Belts, 

" Cylinders, .... 

" Fire Tube BaDers, 

" Mill, . .... 

•' Shafts, 

" Wheels V. Turbine 

Vibrations caused by Horizontal Machin- 
ery 10 

Victor Turbine Wheel, 86, 87 



PAGE. 
386 
509 
518 
107 
. 93 
107 
127 
107 
225 
332 

24 
361 
199 
169 
121 
286, 320 
202 

83 



Virginia Pine, . 
Volume of Air, 
V-Toothed Roll,* 



and Case, complete,* 
•. ase,* 

removed from Case,* 
set in Ordin'y Flume,* 



WALLS, Brick,. 
Batter of, 
" Cost of Stone, 
" Hard Finish for, 
" Holes m, 
" Hollow Brick, 
" HoUow Furnace, 
Waste Steam, Utilization of, . . 

Walnut " . 

Ward's Formula for Burr Dress, 
Washburn Mill, Height of, . 

Washburn A Mill, 

" " Pi-otection against Fire 

" B Mill, Magnets in, ... 
" B and C Mills, Power Required, 
Washing-out Bailers, 

" off Burrs, 
Waste of Bricks, 
" ofi'uel, . 
" of Power, 
Water, Boihng Point of, 
" Evaporation of, . 
" in European and American Wheats, 
" Fall, Gross Power, 

" FaU of 

" FaUs, High 

" Flow of, in Turbines, . 

" Gates, 

" Level, Varying, .... 

" Lifting, 

" Pipes, Fixed, .... 

" Pumping Hot 

" Required by Turbines. 
" Square Inches of, . 
" Trouble from Back, 

" Velocity of, 

" Weight of 

Water-Power, Cost of, at Various Places, 
" " How to Order Wheel for, 

" " Measuring, 

" " Measurement by Floats, 

" " Unsteady, 

Water and Steam Power, Relative Cost, 

Water-Tube Boilers 

Water Spaces, 

Water- Wheels (see under Overshot, Un- 
dershot, Breast, Spiral, Screw, 
Flood, and Turbine). 
Water- Wlieels, Gearing for 

" Kinds of, . . 
" How to Order, 
" vv ith Horizontal Axes 
'1 Ice in, 
" Reaction, 
" Building Overshot, 
" Buckets, Slope of, 
" in Cascade Mills, . 
" of New York Belting and 
Packing Company, . 



75, 



81 



90 

88 

89 

92 

117 

114 

394 



15 

17 

15 

21 

19 

29 

115 

149 

116 

341 

11 

205 

31 

254 

76 

152 

353 

17 

117 

177 

157 

116 

279 

HI 

107 

95 

, 82 

34 

77 

127 

37 

143 

93 

91 

79 

107 

34 

75 

39 

107 

110 

D6 

75 

124 

125 



86 
77 
39 
77 
78 
81 
504 



79 







PAGE. 


Water-Wheels, Work of, by Night and Da 


y. 112 


Governor for, A. W. Woo 


d- 


ward's, 


96 


Shafts for Wmg Gudgeon 


s 


of 


196 


Water m Wheat, 


510 


Watt's Rule for Grate Surface, . 


131 


Weakening Effect of Steam Domes, . 


128 


Wear of Bearings 


245 


•• of Stones, 




325 


Webbing for Packing, . 




171 


Weevils, . . . ■ 




519 


Weight of Air. . 




114 


" of Bricks, 




16 


" of Leather Belts, . 




200 


" of Materials (see under each m 


a- 


terial). . 




'• of Pulleys 


239 


" of Tanks, 


34 


" of Water 


34 


" of Water in Flumes, . 


103 


" of Wood 


117 


Weighting Bm-rs, 


317 


Weirs,* 


109 


• Table for 


110 


" Measurement by, .... 


108 


Wells, Artesian 


34 


West Virginia Bm-r 


288 


Weston Differential Block,* . 


469 


Wet Steam 


125, 164 


Wheat Berry in Section,* 


512 


" Bran of Dry 


279 


■' to Take out Oats from. 


255 


" Oregon, 


254 


" Southern, 


279 


" Treatment of Michigan. 


257 


" to Pui-ify Heated, 


254 


" to Take Oats from Spring, 


256 


" Quantity of Du-t in, 


256 


" Screens for 


264 


•• Brush, Capacities of, . 


278 


" " Champion,* 


277 


" Cleaning Machinery, Inspection of 


11 


" Heaters, Steam, .... 


279 


" •' Durant's Thermometer i 


U- 


tachment for, . 


279 


" " Rice's Generator for,* 


279, 281 


Wheats, water m, 


279 


'■ Dampening 


281 


" Dress for TTnder-Runner,* 


340 


" Foreign Prices in, ... 


254 


" Grinding, 


295 


" Reels for,* 


443 


" Stone for 


288, 289 


■• (Look also under sub-heads, as W 


m- 


ter, Mediterranean, Soft, etc.) 




" Qualities of, 


523 


Wheel, Fly 


201 


" Pit, 


94, 99 


" Sounding for, 


13 


" " of Niagara Falls Mill, . 


53 


Wheels, Gear 


224 


" Water, etc., Niagara Falls Mill* 


52 


" (See also imder Turbine, e' 


C.) 77 


Wheelock Engine,' . . . , 
" Indicator Diagram fror 


179, 180 


Q,* 178 


White Burr 


288 


" Oak 


117 


'• Pine, 


117 


Whiteness of Flour from Rolls, . 


391 


Whitewash for Grubs, .... 


520 


Wide Belts, 


201 


Width of Belt, Influence of. 


199 


Wiebe's Dress,* 


329 


WiUow, Hard 


116 


Windows, 


38 


" Iron, 


20 


" French 


38 


" to Lessen Effects of Explosions, 


38 


Wing Gudgeon for Water-^Mieel Shafts 


* . 196 


Winter Wheat, Cleaning, 


256 


" '■ Jffiichigan, 


523 


" Red Mediterranean, . 


525 


Wire Binder, 


254 


" Bolting Cloth, "Acme,"* . 


429 


" Clothed Reels 


445 


" Cloth for Engine Packing, . 


171 


" Drawing, Steam, Advantages of. 


761 


" " and Throttling, Loss by. 


161 


" in Wheat, 




254 



INDEX. 



Wire Rope, Transmission, . 
Connecting Rod,* 
" General Idea of Sheave,* 
Lining ttie Sheaves,* 
Transmission,* 
" Screens * . . - ■ ■ 
Wisconsin Water for Boilers, 
Wood, Air Required for Burmng, 
" Bm-nt in Mills, . . • ■ 

" as Fuel „ • . 

" 'harcoal. Air Required m Bummg 
" Consumption of 100-bbl. Mill, . 
" Fuel causing Corrosion of Boilers, 
" Lagging for Steam Engines, 
" Pulp Ban-els. . 
" Weight of Cord, . 
Wooden Bearings, Graphite for 
" Flume for Tmbines, 

" Pillars, Strength of, 
" Red-StafC,* 



358 



PAGE. 

iy«, 237 
342 
239 
210 
iMl 
259 
150 
115 
187 
187 
115 
187 
150 
165 
476 
117 
245 

103, 104 

221 

19 

348 



Wooden Shafting ■ 

Woods, Various kinds (See 116. 11 < , and un 

der names of kinds). 
Woodward, A. W, Water-Wheel Governor 
Wood-Working Machinery, Bells upon, 
Work of Bricklayer, per day, 

" of Steam in Cylinder, . . • 
" of Water-Wheels by Night and Day, 
Wrought-Iron Boilers, . • ■ 

Journals, Bearings for, 
" Shafting, 
" Rimmed Pulleys, . 



T'AEGER Mill, Plans of,* . 
" " Loss from I'ire in. 

Yellow Burr Stone, 



58. 



PAGE. 

188 



96 
202 

16 
184 
112 
119 
249 
188 
202 



61, 62 
30 
289 



Flour, ??2 



Pine, 



117 



^~ H- 



Miller, Millwright and Millfurnisher. 



-y- ■=H- 



CHAPTER I. 



MILL CONSTRUCTION. 

Site — Plans — Cost of Excavation — Foundations — Frost — Walls (Stone) — Bricks — Mortar — Batter — 
Partitions — Chimneys— Beams— Floors— Doors and Windows — Sheathing — Plastering— Roofs- 
Leaders — Skylights — Ventilation — Lightning Rods, Etc. — Paints — Fire-Proof Construction — 
Fires and Their Causes — Artesian Wells — Tanks— Pumps — Hose — Hydraulic Ram — Chemical 
Extinguisher— Fixed Water Pipes — Steam Pipes — Heating— Lighting — Estimates. 

Site. — The first thing to do (if the site has not been already chosen), is to 
select a place for the mill. This is too frequently done without proper 
consideration and without regard to the probable effects of circumstances 
which become important factors in determining the success of milling enter- 
prises. It is very difficult to find a place that has all the advantages of 
being near the wheat fields, just on the line of both railroad and water 
connection, with cheap freights from competition, handy for wagon trans- 
portation, with good outlet for the products, cheap fuel, or plentiful, unfail- 
ing and cheap water supply, in such a situation as to make the expense of 
installing the water-wheel low, and all the other items which go to give one 
mill an advantage over another. These things must all be taken into ac- 
-count. But the site once chosen, the next thing is to draw the plans. 

Plans. — What the plan is to be will be determined by what the motive 
power is to be, the kind of Avheat to be milled, whether the mill is to be for 
custom or merchant work, or both combined; where the motive power is ap- 
plied and in what manner; which process or system of milling you have deter- 
mined upon; how the wheat is to be received, whether you are to store great 
quantities of it or not; how the products are to be got out. There is no 
investment that brings so good a return as a .good set of plans. They save 
labor and material in erecting the mill and power and labor in running it. 
Choose the process to suit your condition, the machinery to suit the power, 
and the mill to fit the machines. 

The draught of the mill should first show every wheel, shaft and machine 
and their places, and after this the windows and doors, etc., can be placed. 
The most expensive mill is that which is built without a plan. It is much 
easier to correct a mistake on paper than when in wood, stone or metal. 
The mill should not be planned or built too hastily. The building should 
be adapted to the machinery it is to contain. Not a blow should be struck 
before the whole mill is drawn on paper. In planning, the following ele- 
ments should be considered : Whether the mill is to be steam or water driven, 

2 



12 MILL CONSTRUCTION. 

yard, measured in place (an average cart load), of sandy soil in five minutes; 
loam six minutes ; any of the heavy soils, seven minutes. This would give, 
for a day of ten hours, 120 loads, of 40 cubic yards, of light, sandy soil ; 
100 loads of loam ; or 86 loads of heavy soils. Deducting two-fifths time 
lost, the actual work is 24 yards of sandy soil ; 20 of loam; or 17.2 of 
heavy soil. The cost, at $1 per day, is thus: For sandy soils, 4.167 cents 
per cubic yard ; loam, 5 cents ; heavy soils, clay, etc., 5.81 cents. Next, as 
to hauling, dumping and returning. Horses travel, in hauling, 2\ miles 
per hour, or 200 feet per minute — 100 feet, trip each way. There is a 
loss of 4 minutes in every trip for delay. Thus, to find the number of 
trips per day over any average lot, divide the number of minutes in a work- 
ing day by the sum of 4, added to the number of 100 feet lengths in the lot. 
One driver attends four carts on ordinary leads. This is 25 cents per cart. 
When labor is $1, the horse is generally 75 cents including Sundays and 
rainy days. Spreading. — For cellar work this is seldom done. The bank 
men will spread 50 to 100 cubic yards per day, say \\ cents for heavy soils 
and I cent for light. For keeping the road in good condition for hauling 
as the ruts and puddles should be filled, &c., allow i-io cent per cubic 
yard per 100 feet of lead. Wear, &c., will be covered by ^ cent per cubic 
yard. Superintendents and water-carriers should be covered by \\ cents 
per cubic yard. Wheelbarrows. — Men with barrows move about the 
same as horses. The time of emptying is about i^ minutes, and, in all, we 
may say that a man works only nine-tenths of his time. To find the num- 
ber of barrow loads per day per man, multiply the number of minutes (600) 
in a working day by 9, divide the product by 1.25, the number of 100 feet 
lengths in the land ; divide the number of loads by 14 for the number of 
cubic yards, since the cubic yard, measured in place, makes 14 barrow loads. 
Removing rock excavations by barrow. — A cubic yard of hard rock in 
place weighs 1.8 tons if sandstone or conglomerate, and 2 tons if good com- 
pact granite, gneiss, limestone or marble. Broken up, the solid yard takes up 
if cubic yards. Earth swells to only one and one-fifth its ordinary bulk. 
Such a cubic yard will weigh 1.09 tons; then a barrow load of 2.31 cubic 
feet of loose earth weighs 174 lbs. We may say that a barrow of loose 
rock should weigh 177 lbs. and take up 2 cubic feet of space. For loosen- 
ing hard rock allow 45 cents per cubic yard in place. Soft shales may 
be loosened by pick and plow for from 15 to 20 cents; others may cost %\. 
Quarrying hard rock takes i to ^ lb. of powder per cubic yard in place; 
sometimes \ lb. A good driller will drill 9 to 12 feet deep of holes, 2-2- feet 
deep by 2 inches diameter, per day, in average hard rock, at from 12 to 18 
cents per foot. Removing rock excavations by carts. — A cartload of rock 
is \ cubic yard in place, weighing, say, 851 lbs. As the cart weighs \ ton, 
the loads of rock and of dirt are very nearly the same. 

Foimdations, — The character of foundations is as important a subject 
as can be studied in connection with mill building, and we fear that too little 
attention has been paid to it. The foundation should be thoroughly tested 
with an iron rod or pump auger, to ascertain if the soil is firm. In starting 
the masonry the large stones should, of course, be placed at the bottom of 



EXCA VA TIO.YS—FO UNDA TIONS. 13 

the pit, so as to equalize the pressure as much as possible, and they should 
be carefully bedded, so that they cannot possibly rock. Where a mill is 
built in front of a race, with a yielding bottom, which would be liable to wash 
away in freshets, the entire bottom should be covered with a deposit of rough, 
angular quarry stone, the largest ones being at the outside. In locating a 
mill, the general outlines for the plan of the village, which is often erected for 
the accommodation of the manufacturing population, should be fixed upon. 
The requirements of the little colony, which is frequently formed around the 
waterfall which turns the mill wheel, should be considered, in order that 
there may be an agreeable arrangement of the dwellings. 

The whole extent of the waterfall should be in the first instance located 
and improved as far as practicable, as water power is always valuable ; and 
permanent bounds should be erected at the height of the ordinary level of 
the water in the mill pond to serve as landmarks of possession, should mills 
be afterwards erected in the same vicinit)'. Before fixing upon the immedi- 
ate spot for sinking the wheel pit, the earth around it should be carefully 
sounded by a pointed iron rod, as before mentioned, to ascertain if there are 
ledges of rock which might obstruct the necessary excavations, as by chang- 
ing the location only a few feet obstructions of this sort may commonly be 
avoided. Although it is desirable to place the foundation of a mill upon this 
solid basis, yet a little attention to this may save the subsequent expendi- 
ture of large sums, which are very frequently lost by the costly excavations 
in flinty rocks. In laying out the ground plot for stone or brick mills the 
trenches should be staked out considerably larger than the intended size of 
the building to allow of the projection of one or two feet for the foundation 
stones, which, on loose soil, should extend considerably beyond the outer 
face of the main walls. If the lower courses of stone work, intended for the 
foundations beneath the surface of the ground, be three feet wider than the 
wall above it, then two feet of the projection should extend beyond the 
outer fronts of the walls and only one foot within them. Walls of buildings 
have always a tendency to spring off or outwards, but are effectually pre- 
vented from falling inward by the floors. Even after the utmost caution has 
been bestowed in laying the foundations of a mill with large heavy stones, the 
walls should be secured to the ends of the beams by iron clamps or screw 
bolts and plates, to prevent them from springing outward. AValls sufficiently 
strong for warehouses have been found to yield at last to the constant tremor 
produced by the reciprocating motions of machinery and the violent sudden 
thrusts occasioned by the irregular action of the teeth of wheels. 

The arches above the flume and race of a mill, unless constructed near 
the centre of the building, with each wing to serve as a buttress, are always 
inclined to yield to the weight pressing upon them, whereby one of the 
buttresses forming the end wall is commonly crowded off. The tremor 
of the walls affects the stones of the arch, the least yielding or opening 
of which allows the keystones to operate in an instant like so many wedges 
to prevent the span from recovering its former place, whereby the walls soon 
become seamed with unsightly cracks. It is better to form two small arches, 
or to support the centre by stone pillars, than to form one large span. 



14 MILL CONSTRUCTION. 

When the soil is composed of loose sand or clayey loam, the walls of the 
wheel pit should be founded upon piles, and in most cases it is common 
to extend the planked floor of the wheel pit sufficiently for the surrounding 
walls to be based upon it. Indeed it may be adopted as a general rule that 
it is true economy to construct all parts of the foundations of mills in 
the strongest and most solid manner. 

The posts which support the beams in the centre of a mill should also 
rest upon a very solid mass of masonry, as the lines of shafts and other mill 
gearing are either attached or dependent upon them for maintaining their 
proper situations. The settling of a pillar in the basement of a mill merely 
one-half of an inch will derange all the lines of horizontal shafts in every 
story above, whereby vast stress is thrown upon the couplings, and all the 
revolving wheels connected with such shafts immediately begin to wear 
irregularly and to produce a clattering noise. If a block of hewn stone be 
used in any part of the structure, it should not be omitted here. Cast-iron 
pillars or posts are generally used in England, and as they are cast hollow, 
like water pipes, they are not very expensive. 

Great care is bestowed in laying the most solid foundations of hewn 
stone, to sustain the working parts of the steam engines and water wheels, in 
the best foreign mills. Blocks of split granite, plumber blocks and other 
heavy fixtures for water wheels may be formed of granite at an expense 
Avhich will not prove eventually much greater than if formed of timber, a 
material which in such situations is very liable to rapid decay. In setting 
up water wheels and steam engines, particular care should be given to the 
construction of the framing — which sustains the first impulse, or immediate 
action of the moving force — as independent of the walls and floors of the 
mill as possible, in order to avoid imparting to the whole building the tremor 
which is frequently so great as to be communicated in a very perceptible 
manner to the ground upon which the building rests. 

Frost. — One of the most difficult problems which present themselves to 
architects and builders is the determination of the question, how soon mason 
work ought to be stopped on account of frosts. For extensive buildings, the 
erection of which will, at the best, occupy several seasons, the ordinary rule 
of covering over the walls from November to April is well enough ; but 
in smaller structures, such as dwelling-houses and mercantile buildings, 
where every day's delay involves a money penalty or a loss of rent, it 
is of great importance to continue operations as long as is consistent with 
safety. In practice, many contractors never cease building as long as 
the mortar can be made to remain unfrozen long enough to spread it ; 
but this course involves great risk, not perhaps of the failure of the walls so 
constructed, but because of the danger of permanently weakening them, and 
rendering them porous and permeable to moisture. A brick or stone chilled 
by cold weather, and laid even in hot mortar, condenses the moisture on its 
surface, where it freezes, forming a film of ice between itself and the bed of 
mortar, which, unless very soon thawed again before the lime begins 
to harden, effects a permanent separation between the brick and the mortar, 
so that it can be lifted from .its bed after the masonry is dry, without 



FROST— WALLS. 15 

the mortar's adhering to it. If a wall so laid is exposed to the sun, so 
as to thaw one side partially, it will bend toward that side, sometimes 
to a serious extent. Cement, although useful for cold weather work on 
account of the rapidity with which it hardens so as to be out of danger, 
is very injuriously affected if frozen too quickly, the "initial set" being 
so broken up as to prevent subsequent induration. No doubt the safest 
mode of conducting winter work is to heat the brick or stone by piling them 
in a sheltered place near a stove. The warmth which they slowly acquire is 
retained for a very long time, especially in the interior of walls laid with 
them, and a superficial freezing, if it should take place, is easily remedied by 
pointing when milder weather returns. 

"Walls. — The walls may be constructed of stone, concrete, brick or 
wood frame. Of these four, brick is the only one which is in any degree 
fire-proof. The cost of stone work may be divided into getting out from the 
quarry, dressing, hauling, mortar, and laying — including scaffold, &c. The 
cost of stone after getting the quarry, cleaning off the top earth to the 
disintegrated top rock, and providing the necessary tools, trucks, cranes, &c., 
may be divided as follows : Stones of such size as two men can lift, 
measured in place, cost about as much as from one-fourth to one- half the daily 
wages of the quarry laborer. Large stones, of dimension from one-half to 
one cubic yard each, on which most of the work must be done by wedges, 
to make them true to shape and dimensions, cost from two to four 
daily wages per cubic yard. (The smaller prices are low for sandstone and 
the greater are high for granite.) One and one-third cubic yards of good 
sandstone can be got out at the same cost as one of granite ; that is, calling 
the price of granite i, that of sandstone will be f ; so that the prices given 
are full for sandstone, scant for granite, and about fair for limestone or 
for marble. 

The waste in dressing stone will be from one-sixth to one-fourth of the 
rough block, in the best cases. In blocks of half a cubic yard each got out 
by blasting, one-fourth to one-third will not be too much for medium stone. 
It is better to dress at the quarry, so as to save transportation. A stone cutter 
will take out of wind and patent hammer dress 8 to lo square feet of plain 
face in hard granite in eight hours, or twice as much of the dress given butts 
and joints. In good sandstone or marble he can do about one-fourth more. 

In estimating the cost of ashlar facing masonry, stones, say 5 x 2 x 1.4 feet 
thick, equal to 4- cubic yard each, will cost for granite or gneiss : 
Getting out the stone from the quarry by blasting, allowing one- 
fourth for Avaste in dressing, i^ cubic yards at $3 per cubic yard, §4.00 
Dressing 14 square feet of face at 35c., . . . .4.90 

" 52 " " butts and joints at 1 8c., . . 9.36 

Net cost of the dressed stone at the quarry, . 
Hauling, say one mile, loading and unloading. 
Mortar, ........ 

Laying, including scaffold, hoisting, machinery, &c., 

Net cost, . ". . . . . . $21.86 



$18. 


.26 


I 


.20 




.40 


2 


.00 



16 



MILL CONS TR UC TION. 



With stones of a smaller size than that before mentioned there will 

be more square feet of dressing per cubic yard. 

Following is the estimated cost of large scabbled masonry : 

Granite rubble, stones \ cubic yard each, cost for getting the stone 
from the quarry by blasting, allowing one-eighth for waste, i 1-7 
cubic yards at $3, . . . . . . . I3.43 

Hauling one mile, loading and unloading, . . . 1.20 

Mortar (2 cubic feet or 1.6 struck bushels of quicklime and 10 cubic 

feet or 8 struck bushels of sand or gravel, and making), . . i .50 

Scabbling and laying, including scaffold, hoisting, machinery, &c., 2.50 



Net cost, ....... $8.63 

Bricks. — A good hand-pressed brick, 8:| x 4 x 2 inches, weighs 4I- pounds, 
or 118 pounds per cubic foot. A machine brick of the same size weighs 5 
pounds. Either of them will absorb half to three-quarters of a pound 
of water. Brick work may be put at 1.4 tons per cubic yard, 1.3 tons per 
perch of 25 cubic feet, or 116 pounds per cubic foot ; or for machine-molded 
bricks, 1.56 tons per cubic yard, 1.44 tons per perch, and 129 pounds per 
cubic foot. Allowing for waste in cutting to fit corners, jambs, &c., the 
average number of 8:|- x 4 x 2 inch bricks per square foot of wall is : 



Thickness of Wall. 


No. of 
Bricks. 


Thickness of Wall. 


No. of 
Bricks. 


8^ inch or i brick. 

123/ " ly^ " 
17 " 2 


14 
21 
28 


21'^ inch or 2^ bricks. 
25^ " 3 


35 
42 



A bricklayer, with a laborer to keep him supplied with materials, will, on 
common walls, lay about 1,500 bricks in ten hours ; in neater faces, about 
1,000 to 1,200 ; in straight fronts, 800 to 1,000 ; in large arches, 1,500 
or 3 cubic yards. 

Good, well burnt bricks will ring when struck together. A soft brick will 
crush with 450 to 600 pounds per square inch, or 30 to 40 tons per square 
foot, while a good machine-made brick will require about 6,222 pounds 
per square inch, or 400 tons per square foot. This last is about the same as 
the best sandstone, two-thirds as much as the best marbles or limestones, and 
one-half as much as the best granites. But masses of brick crush under less 
pressure than single bricks. Small cubical masses, 9 inches on edge, laid in 
cement crushed under 27 to 40 tons per square foot. Piers, 9 inches square, 
27 inches high, in cement, require 44 to 62 tons to crush them ; but cracking 
and splitting commence under about one-half the crushing loads. To 
be safe, the load should not be more than about one-eighth or one-tenth the 
crushing load. 

Bricks should be of regular size, color and shape, with sharp edges 
and corners, and should give a clear metallic ring when struck together. 
They should break clean and show an even grain, without any stones or 



BRICKS— MOR TAR—BA TTER, E TC. 



17 



large pores in them. Most machine-made bricks are heavier and stronger 
than hand-made. 

Mortar. — Mortar is made of about one measure of quicklime (lump 
or ground) to five measures of sand. The bulk of the mixed mortar exceeds 
that of the dry loose sand alone about one-eighth. Allowing for waste, 20 
cubic feet or 16 struck bushels of sand of 4 cubic feet and 3.2 struck bushels 
of quicklime f^measure slightly shaken) mkke about 22+ cubic feet of mortar, 
sufficient to lay 1,000 bricks, 8^ x 4 x 2 inches, with the joints used in inner 
walls (varying from f to -^ inch). With such joints 1,000 such bricks make 2 
cubic yards of massive work, and nearly one-third of the mass will be mortar. 
For outside joints, more lime is used ; say one in four or even one in 
three parts. For cellar walls of stone rubble, one measure of lime to six or 
eight of gravel is used. A cubic yard of rubble requires as much mortar as 
500 bricks of the size given above ; or 10 cubic feet is equal to 8 struck bushels 
of sand and 2 cubic feet or 1.6 bushels of lime. The best laid rubble 
will contain only one-fifth of its bulk of mortar, or 5-J- cubic feet of sand and 
I.I cubic feet of lime per cubic yard. To resist dampness, hydraulic lime 
should replace one-third of the lime. If exposed to water, still more cement 
should be used. With bricks 8^^ x 4 x 2 inches, the quantities of mortar, as 
compared with the whole mass, to the number of bricks required for a cubic 
yard of massive work should be in the proportion stated under : 



Thickness 

of 

Joints. 


Proportion of 

Mortar in the 

Whole Mass. 


Number Briclcs 

per 

Cubic Yard. 


Number Bricks 

per 

Cubic Foot. 


•^-inch. 


About 1-9 


638 


23.63 


H " 


■' Y 


574 


21.26 


H " 


" 3-10 


522 


19-33 


Yz " 


" Y 


475 


17.60 


H " 


" 4-10 


433 


16.04 



Allow 2 or 3 per cent, of the brick for waste ; in common buildings 5 per 
cent, or more. Common lime mortar exposed to constant moisture will 
never harden ; cement does. Fine brickdust or burnt clay improves common 
mortar and makes it hydraulic. The crushing force of good mortar is about 
50 tons per square foot, or 777 pounds per square inch. 

Batter. — The walls of each story should be a little lighter than those of 
the story below, and the foundation should be heavier (that is, much thicker 
and stronger) than the wall which it supports. Thus, a 14-inch wall should 
have an 18-inch foundation. A good way, for many reasons, is to give the 
foundation wall a batter or slope, the inside bemg straight and the outside 
having all of the batter. Where each wall is slightly heavier than the one 
above it, the outside face should be flush. The corbel or inside ledge can 
serve in part as the support of the floor beams. 

Hollow Brick Partitions. — Some idea of the value of hollow bricks 
in fire-proof constructions can be drawn from the following report of experi- 
ments, attested by numerous architects and insurance officers in New York : 
In a building with wooden beams and rafters, a fire of pine and hickory 



18 MILL CONSTRUCTION. 

logs, kerosene and shavings, was maintained for one hour and then put out. 
On examination the floor beams and ceiling rafters were found to be even 
undiscolored by the heat. A Mansard roof, laid on wooden rafters and lined 
inside and out with hollow bricks, sustained a fire of logs and kerosene on 
both sides for thirty-five minutes without injury or even discoloration. 
Some pieces of pine wood were placed in a hollow brick, the ends of which 
were stopped with cement. The brick was then placed in the fire and kept 
there for thirty-five minutes. On being taken out it was found to be un- 
injured. Experiments with wood shavings, paper, etc., showed similar 
results. 

Chimneys. — These will be spoken of more fully under the head of 
boilers. Chimneys, which are intended simply as smoke passages for a heat- 
ing apparatus, demand much less science in their design and erection than 
those intended for boilers. In a brick or stone mill they should form a part 
of one of the outer walls. Where they have any considerable height above 
the rest of the building they should have an extra foundation to bear the 
extra weight. They should be built plumb and true, with close joints, well 
laid up in good mortar, and with none of the mortar projecting on either the 
inner or the outer face, as any roughness tends to retard the upward passage 
of the products of combustion. The higher the chimney the better the 
draught. If a chimney is placed at the windward side of a building, in such 
a place that it will receive a reflected current from a crest, or if it is in any 
place where it is liable to receive such a reflected current, it must be made 
sufficiently high to prevent a high wind from blowing the 
smoke down it. There are places where it is necessary to 
have a cowl to assist the draught; but in most places it is 
enough to have a very simple contrivance of brick work, so 
placed that the upward draught of the chimney will have 
more force the stronger the wind blows. Such a structure 
will be something like the diagram shown; with the open side of the gable to 
the prevailing wind. If there is no prevailing wind and the draught is poor,, 
then a revolving cowl must be used. Of this there are many samples and 
many excellent patterns. 

Strength, of Beams. — Calling the breaking load of a beam, firmly 
fixed at one end and loaded at the other, i; when evenly loaded it will be 2; 
when merely supported at the end and loaded at the centre, 4; supported 
at the ends and with the load evenly and uniformly distributed, 8; firmly 
fixed at the ends and loaded at the centre, 8; if uniformly loaded, 16. 

The Hodgkinson beam is nearly one and three-quarter times as strong as 
an ordinary beam of equal weight, with both flanges alike. 
As cast iron requires six and a half times as much weight to 
crush it as to pull it apart, in the Hodgkinson beam the 
upper or compressed flange has only one-sixth the area of 
the lower one. Thick castings are proportionately weaker 
than thin ones. For very long beams half the weight of the 
beam must be deducted to get the net breaking load. 
Where the weigbt is evenly distributed, the breaking weight will be twice as 




CHIMNEYS— BEAMS— FLOORS. 19 

great. Cast beams must always be tested. The strength of wooden pillars 
and beams depends upon the seasoning. This should be borne in mind in 
building with green timber, for seasoned timber has often twice the strength 
of green. 

One precaution that is very seldom taken with high buildings is so sup- 
porting the timbers of the floor that in case they break or fall they shall not 
pry the wall over inward, and that in case they expand they will not push it 
over outward. As ordinarily constructed, holes are left in the walls into 
which the ends of the joists are set, the holes being about the size of the 
ends of the joists, so that in case the floor falls the timbers are apt to tumble 
the walls inwards on the contents of the building. There are two ways of 
getting around this. One is to set the end of the joist upon a corbel or 
projection from the face of the wall so that the joist will clear the face of 
the wall entirely, and in case of fall exert no influence upon the wall. 
The other method has the same object in view and accomplishes it by a 
simpler method. The holes to receive the joists are made about twice as 
high as the joists, so that in falling the joists have no prying effect upon the 
wall. These remarks apply to iron as well as wooden beams; but for iron 
beams there should be the additional precaution to leave a greater space be- 
tween the end of the beam and the wall, so that the inevitable expansion of 
the beam from fire shall not cause an outward thrust tending to overthrow 
the walls. It would perhaps be as well if all external walls were held 
together by anchor bolts with external plates, which, although not very 
sightly, often help to hold the wall up when otherwise it would topple and 
fall outward. Of course, if the beams are properly cased below with some 
fire-proof material or by some heat-proof method, their expansion will be 
very much less than if they are left naked to the action of the heat. 

Floors. — The longer lumber is seasoned the better will it be, and it will 
give less trouble by checking, warping, sagging, and shrinking. Air or water 
seasoned lumber is better than that which has been kiln-dried. Making 
beams strong enough n(5t to break does not provide against their sagging. 
All wooden floor beams should be sawed and set on a " camber," that is, with 
a slight rise in the middle, and when the weight is put on them they 
will settle to a level. The greener the timber, the more camber will have to 
be given. The upper floors must be more cambered than the lower. Depth, 
rather than thickness, gives strength and stiffness to floor beams, and 
they may be greatly strengthened by plenty of cross braces, which cost little 
but add greatly to the stiffness and strength of the floor. Any sagging in the 
mill throws all of the machinery out of line and consumes power. 

Where posts are employed to hold up floors, they should be as stiff 
as possible, but they must not be made to take up too much floor space. 
This does not mean that they must be of small section, but they shall 
be disposed so as not to prevent the proper arrangement of machines. 
Really, the floor plans should be laid out as though it was possible to get one 
large floor that would not need posts ; and then the posts should be made to 
conform to the machinery. If the floor beams are made stiff and are well 
scarfed and properly supported, the columns can be shifted when the mill or 



20 



MILL CONSTRUCTION. 



machinery is altered, without greatly interfering with the strength of the 
building. Floors for storing flour must be extra strong; as the weight is 
extremely concentrated. 

As fire-proof floors are necessary features of construction in a first-class 
mill, some figures of their weights and prices will be found useful in making 
estimates. For ordinary spans between beams of, say, 5 to 6 feet, there 
are generally used 6-inch flat arches of either lime of Teil, or hollow burnt 
terra cotta in 5-feet spans, and 8-inch arches of same description in 6-feet 
spans. These flat arches offer a flat surface on both top and bottom sides, 
and, therefore, give a flat ceiling, left ready for plastering. Their compar- 
ative weight and cost, compared with ordinary solid brick segmental arches, 
filled up with concrete above them, are as follows : 



Description. 


Weight 

per 

Square Ft. 


Price 

Put Up in 

Philadelphia. 


6-inch lime of Teil flat arches, .... 
6-inch burnt terra cotta, . . . ■ . 
8-inch lime of Teil flat arches, .... 

8-inch burnt terra cotta 

Segmental ordinary arches with concrete filling, 


22 lbs. 

34 " 
28 " 
42 " 
65 " 


27 cents. 

28 " 
30^4 " 
33 " 
20 " 



The great lightness of the flat arches, and the fact of their presenting a 
flat ceiling, all ready for plastering, has caused them to supersede very largely, 
in first-class buildings, the ordinary segmental brick and concrete filling 
arches that load the beams for no needful object, and present when erected 
curved surfaces between beams, ^ — n^- — -v.- — n^- — -s; which construction admits 
of a very ordinary and plain finish. 

Iron Doors and Windows. — Few buildings stand in greater danger 
of fire than grist mills, and yet very few mills have anything like adequate 
protection therefrom. Window openings, while they give outlet to flame, 
give inlet to air which carries a fire further and with greater force. The 
flames from one window sel fire to the one above, and so on. It should 
be made imperative that the doors and shutters of a mill shall be fire-proof. 
To take d6wn the windows and coat them with a thin sheet-iron looks 
all well enough, but a real fire passes by such trifles. Thin sheet-iron 
gets red hot in a minute, and the wood readily chars, affording protection 
merely for a moment. Of course the next best thing is to make them of iron, 
stiff enough to need no reenforcing of wood. But here comes in anothef 
difficulty ; this iron warps and twists under the action of fire; and even if it 
does not cause great loss by fire direct, the shutters are useless after the fire, 
and must be thrown away. To make matters better, corrugated iron shutters 
are employed, because they are much stiffer and stronger, besides being more 
sightly. But even they have this disadvantage, that iron is a good conductor, 
and they speedily get red hot on both sides, so that a fire from the outside 
may set fire, to combustible material inside, even with the shutters closed. 



WINDO WS—SHEA THING— PLASTERING. 21 

The next step toward the perfection of fire-proof shutters is to make 
air chambers between two corrugated walls, thus giving greater stiffness, and 
at the same time preserving one side from destruction or great heating by the 
non-conducting layer of air between. Such a shutter is at once more 
fire-proof and more burglar-proof than any of the others indicated. In some 
cases the principle is carried still further by employing three corrugated 
sheets, thus giving two air spaces, and securing greater strength. In these 
last two modes of construction one of the sheets is larger than the others, so 
as to form a flange that will completely cover the opening of the window, 
thus making at once a neater job and one more fire-proof and better adapted 
to resist burglars. All openings in the walls of buildings that contain 
valuable matter and are subject to fire should be covered by such double or 
triple corrugated iron screens. Where there is an opening between two 
buildings, or between two compartments of the same building, or in any case 
where the opening is a large one, — the door should be a sliding one, 
as no amount of twisting or warping could make it give so as to admit flame 
or a burglar. The corrugated sheets may be galvanized, or they may 
be protected by three or even two coats of good metallic or other resistant 
paint, which will keep them from damage or destruction by rust. 

Sh.eath.ing. — All frame buildings should be properly sheathed to secure 
warmth and dryness. One way of effecting this is to use diagonal inch 
boards over all the studding before the weather boards are put on. The 
diagonal boards have the advantage of making the building much stronger 
and stiff er than it would be if there were no such braces. This point alone 
would make it worth while to sheathe a building Avith boards. The diagonal 
boards may be supplemented with tarred paper or its equivalent run 
lengthwise vertically. The quantity of boards required to sheathe an 
ordinary frame building is somewhat in excess of the exact superficies of the 
sides, by reason of the small quantities cut off on the sides and over windows 
and doors. Filling is often resorted to between the sheathing and the 
plaster. Frame buildings may be filled with brick, rubble, or concrete, which 
of course tends to increase the weight and stiffness of the walls as well 
as their thickness. 

Plastering. — There should generally be given three coats of mortar — 
first the rough or scratch coat of one measure of quicklime to four of sand, 
and one-third of hair to increase adhesion. This coat, three-eighths to one- 
half inch thick, is put on roughly, and should be well troweled and clinched 
behind the laths — which last should be no nearer together than half an inch. 
When nearly dry this first coat is scratched with a pointed stick in lines two 
inches apart. These scratches hold the second coat, which is of the same 
material as the first, but from one-fourth to three-eighths of an inch thick. 
Before it is dry it is roughened by a hickory broom, to hold the third coat. 
The third coat, of only one-eighth of an inch thickness, contains no hair but 
more lime, or one measure of lime to two of sand. Instead of this, the 
outer coat may be a "hard finish," made of one measure of ground plaster of 
paris to two of quicklime, and no hair. A good effect is produced by only 
two coats of plaster, in which fine, clean, screened gravel is used instead of 



22 



MILL CONSTRUCTION. 



sand. As salt would make the walls damp, care must be taken not to get 
plaster hair from salted hides nor to use sea sand. Where a brick wall is to 
be plastered the joints should be left very rough, that the mortar may hold. 
When put on smooth walls the mortar should first be well raked out. A 
plasterer, with one or two laborers for mixing and supplying the material, 
can average from loo to 200 square yards a day of first coat ; two-thirds this 
quantity of second, and half as much of third. 

Plastering laths are generally of white or yellow pine, either three or 
four feet long, one and a half inch wide and one-fourth inch thick. They 
are nailed up horizontally, a half inch apart. The distance between the 
joists is generally fifteen inches between centres, so that the ends of the laths 
may be nailed to them. Laths are sold either by the bundle or by the thou- 
sand. A square foot of surface takes one and a half 4-foot laths ; that is, 
1,000 laths cover 666 square feet. A good carpenter can nail up forty to 
sixty square yards in ten hours. The following table gives the cost of 
plastering : 





Three Coats 


Two Coats 


Material. 


Hard Finished Work. 


Slipped Coat Finish. 


Quicklime, 


4 casks, 


$4.00 


3^ casks, 


$3-33 


for fine stuff. . 


% " ■ 


0.85 




. 


Plaster of paris, 


'A " 


0.70 


. 




Laths 


2,000, 


4.00 


2,000, . 


4.00 


Hair, .... 


4 bushels, . 


0.80 


3 bushels, 


0.60 


Common sand, . 


7 loads, . 


2.00 


6 loads, 


1.80 


White sand, 


2j4 bushels, 


0.25 


. 




Nails, 


13 lbs., . 


0.90 


13 lbs., 


o.go 


Masons' labor, 


4 days, 


7.00 


3>^ days, 


6.12 


Laborer, . . . . 


3 days, . 


3.00 


2 " 


2.00 


Cartage, .... 


• 


2.00 


. 


1.20 



Roofs. — The roof of any building should be designed with a view 
to utility, after which questions of cost or of beauty may come in the order 
which bests suits the owner. In mill building, the attic is generally used for 
some machinery or other, and hence the elevation of the building should not 
be planned until the floor plans are laid out with special reference to 
the machinery which is to be employed at first and subsequently. A 
little head room in the attic costs very little when it comes right down 
to a question of rafters and slate. Extra height of the attic means at the most 
only a little extra cost for wall, if a certain pitch of roof is determined upon ; 
but if the wall height is decided, a little steeper pitch of roof by slightly 
longer rafters will give more light and head room with but little cost, beside 
shedding rain and snow better than the flatter pitch. There is one thing to 
be borne in mind — the pitch and the material of the roof ought to agree. A 
slate roof will not bear to be made flat, nor a gravel and tar one steep. If 
the roof is of slate, the rafters must be made heavy enough to bear the extra 



PLASTERING— ROOFS. 23 

weight of the heavy covering. If there are snows that come to stay, 
fiat roofs of no material will answer well. It must be remembered also that the 
roof is one of the first points attacked by fire from without and one of the 
most common means of spreading fire from either within or without. If put 
on in a windy locality, it must be more securely fastened on than in a locality 
where there are no high winds. Every roof should be put on with a view to 
be raised one or more stories at some time or other, for it often happens that 
it becomes absolutely necessary to have more room in the mill, and that land 
cannot be bought at any price. If the foundations are strong and the walls 
heavy enough to bear the weight of another story, and the roof stiff enough 
to bear lifting, so much the better. In every case there should be ample 
provision made for getting out on the roof in case of fire, and for inspection, 
&c. It is very easy to arrange trap-doors for egress, with ladders for getting 
up to or down from a roof; and while these do not cost much at first, 
they are — especially the trap-doors — somewhat expensive to add afterwards. 

Of course, the pitch of the roof must be made to correspond not only 
with its material, but with the general style of the building, with the climate, 
with the uses to which the attic is to be put, &c. Other things being equal, 
the colder the climate, and the greater the liability to snow upon the roof and 
to driving storms, the steeper the pitch of the roof should be. There is, 
however, a certain limit to this ; as, the steeper the roof is, the greater 
the resistance to high winds, the greater the weight put upon the walls, 
and the greater the liability of the covering being torn off. 

A flat roof never means a roof that is exactly flat, but one with but little 
pitch. This style is but little suited to districts where there is much or any 
snow fall, as the snow will lie for a; long time upon it and is apt to leak 
through, in time of thaw, even if it does not by its great weight crush the 
timbers and covering. A flat roof has the advantage of being cheap to con- 
struct, as to both material and labor. 

The tin roof, so called, is a covering of tinned sheet-iron; at least, it is 
nominally tinned sheet-iron, although lead enters more largely into the com- 
position than the higher priced tin. Owing to the utter refusal of tinners to 
adopt improved and money saving methods of putting on so called "tin" 
roofs, the old fashioned system of using small sheets of tin, which must be 
carefully bent up on the edges and soldered in place, still remains, although a 
much cheaper and tighter roof can be made from the continuous rolls of 
tinned iron supplied by some English manufacturers. The table on next page 
gives the size, quality and weight of tin sheets used in roofing. The quantity 
required of each size to cover i,ooo square feet is given, and the number of 
square feet that a box of each size will cover. It should be remarked that 
the tin covering of roofs should receive a coat of good resisting metallic 
paint, ground in oil, applied above and below. 

The iron roof, famiharly so called, consists of an iron covering on a 
wooden frame work. As generally applied, the purlins are sheathed with 
board (sometimes with both board and sheathing paper or felt), and then the 
rolls of sheet-iron, properly painted on both sides, are applied in such a 
manner as to make tight joints along the seam ridges. 



24 



MILL CONSTRUCTION. 



TABLE OF SIZES, WEIGHTS, ETC., OF TIN SHEETS. 



Mark. 


Number of 
Sheets 
in Box. 


Dimensions. 


Weight 
Box. 


Length. 


Breadth. 


IC, . 

lie, 

IIIC, . 

IX, . . 

IXX, . 

IXXX, . 

IXXXX, . 

DC, 

DX, . 

DXX, . 

DXXX, . 

DXXXX, 

5 DC, . . 

5 DX, . 

5 DXX, . 

5 DXXX, 

5 DXXXX, 

ICW, . 


225 
225 
225 
225 
225 
225 
225 
100 

100 

100 
100 
100 
200 
200 
200 
200 
200 
225 


Ins. 

13X 
12^ 

13^ 
131^ 
13^ 
i3?4^ 
16K 

163/ 

16/ 
16^ 

16/ 

15 

15 

15 

15 

15 

13.3^ 


Ins. 
10 

^% 

10 ^ 
10 
10 
10 

I2K 

12>^ 

12K 

11 

II 

II 

II 

II 

10 


Lbs. 
112 

105 
98 
140 
161 
182 
203 
105 
126 

147 
168 
189 
168 
189 
210 
231 
252 
112 


A box of 225 sheets, 13% x 10, contains 214.84 square feet ; but, allowing 
for seams, it will cover but 150 square feet of roof. To find area of roof 
covered by any size sheet, deduct 2 inches from its width and i inch from 
its length. A roof covered with tin or other metal should slope not less 
than 1 inch to a foot. 



Leaders. — Leaders should be as large in diameter as they can well be 
made, so as to insure carrying off the rain or melted snow as fast as may be 
demanded. If small, they are not only apt to carry off the rain too slowly, 
but to become clogged with leaves or other obstructions, and in freezing 
weather to become full of ice, which causes bursting and leakage and general 
disfigurement or damage. For preventing this, the most sensible pipe has 
lengthwise corrugations, preventing its bursting by permitting it to " give " 
with the expansion of the frozen water, so as not to cause any rupture of the 
pipe itself. The leaders should have ample connection at the ground, and 
the tops should be covered with a basket of wire, to keej) out leaves, pieces 
of paper, etc. 

Skyligllts. — If there is any one operation that does require light it is 
that of cleaning grain; but we often find cleaning machinery in an attic, re- 
quiring the aid of a lamp or candle, with its attendant dangers, to see what is 
going on. To prevent this, skylights, which afford perfect protection from 
the weather, while giving all the light required for this primary operation in 
milling, may be used. 

Ventilation, — No building in which human beings pass their time 
should be without means of change of air. In flour mills, no matter how 
carefully the. machines are cased in, there is a great quantity of fine flour dust 



VENTILA TION— LIGHTNING RODS. 25 

floating around, and this is breathed in each minute by those in the mill. If 
there is some means of changing the air, the quantity of this fine dust 
is materially lessened and the effect on the lungs is less injurious. "Although 
carefully prepared statistics show that lung troubles resulting from working 
in a dusty atmosphere are not so prevalent among millers as in many other 
similar occupations, yet the influence of mill dust upon the health of the 
miller is of enough importance to demand attention. The sunbeams in 
a darkened room reveal the large amount of dust which is imperceptibly 
inhaled, even under ordinary circumstances, in the common living-room of a 
dwelling. How much greater is the quantity found in a mill or factory, 
where every nook, corner, sill, and rafter is saturated, so to speak, with 
the finest, almost impalpable, dust, which the slightest jar or breeze whiffs 
into the nostrils of the workman. Beside the mechanical irritation occasioned 
by these particles, detrimental effects result from their decay, and chronic 
impairment of health often ensues from dust thus inhaled. The constant 
exposure of millers to mill dust enfeebles the air vessels and often leads 
to deposits, which become a serious embarrassment later in life. Evidence of 
their vocation is frequently found in their lungs ; and it is asserted that many 
a man can have his occupation thus determined long after he has retired 
from the trade of his early or middle life. A physician relates that the 
proprietor of a drug mill, whom he attended, who had left his work ten years 
before, still showed in his sputa the marks of his business. Various forms of 
respirators, designed to be worn over the nose or mouth, have been devised 
for the protection of dust-workers. Users of grindstones and emery wheels 
in large factories are compelled to use something of this nature. Sometimes 
a porous sponge is employed ; at others, an artificial hair moustache is used. 
The habit of thoroughly washing out the mouth and nostrils at noon and 
night, if not oftener, is urged upon workmen thus exposed. While at work, 
the miller should keep the mouth shut and breathe wholly through the 
nostrils. The hairy or ciliary provision in the nostrils keeps much of 
the dust from going into the lungs, and a hairy upper lip is not without 
advantage in this respect. Dust-workers are reminded that the lungs perform 
a function no less vital than that of the stomach. Their structure being 
more delicate than that of the stomach, the access to the blood and to 
the life is more direct. It, therefore, behooves the miller to endeavor 
not to absorb any more of the disturbing , element into his lungs than 
the greatest care consistent with his occupation will permit, and to adopt 
such simple measures for protection as above suggested." There are many 
systems of ventilation employed, and many which do not ventilate at all. It 
must be borne in mind that a system that will ventilate well in summer is apt 
to totally fail in winter, because the conditions are very different. Ventilation 
by keeping the air uniformly dry aids very much the action of the bolts. 

Liiglltning Hods, — With the advances in practical science, much of 
the mystery and uncertainty attending the use of lightning rods have been 
done away with, so that now they are indispensable to almost every building, 
and when properly applied are a good protection thereto. Lightning rods 
are especially desirable on a flour mill, where the air is likely to be filled with 

3 



26 MILL CONSTRUCTION. 

flying dust, and hence explosive or at least inflammable by any spark of fire. 
There are a great number of rods in the market, varying in composition, 
construction and modes of joining. The makers of each one try to persuade 
property holders that in their rod, only, lies complete safety from lightning 
stroke. As a general principle it may be laid down that any system of 
metallic connection between the large reservoirs of water below the first 
stratum of the earth will, if properly accompanied by a system of points 
above the roof line, give immunity from lightning. A metal roof connecting 
with the water leaders, which in turn connect with the iron water or gas 
mains, constitutes, when these surfaces are well wetted by the rain accompany- 
ing a thunder storm, a perfect protection, — requiring only that these rods 
should be properly connected, based, and pointed. A rod is said to protect 
a radius about it equal to double its height ; thus a rod projecting ten 
feet above the roof will protect a circle of forty feet diameter. Sections of 
the rod should be put together by brazing, by riveting, or by well fitting 
screwed joints. There is no use in having a good rod, well placed and well 
pointed, unless the ground connection is perfect. This cannot be too 
strongly insisted upon. The greater the cross section and exterior surface of 
a rod, the greater its conducting and protecting powers. 

The late Professor John Wise, an eminent balloonist, but no electrician, 
collected statistics of many buildings, with rods, that were struck by lightning. 
He gave his own opinion on this subject before the section of meteorology of 
the Franklin Institute, and he had the subject of his own remarks published 
in the daily parsers. His erroneous views never received even the shadow of 
indorsement from the Institute ; but they led to the appointment of a com- 
mittee to report on " The visible effects of and damage by lightning, and the 
feasibility of certain protection of property and life." This committee was 
composed of the following named members: J- B. Burleigh, LL.D., elec- 
trician and author, chairman ; Charles M. Cresson, M. D., physicist and ex- 
pert ; William H. Wahl, Ph. D., formerly secretary of the Institute, and an 
eminent scientist; David Brooks, inventor and telegraphic expert; Robert 
Grimshaw, Ph. D., author and scientific expert. It has just completed with 
great care a voluminous report. The research, extended statistics and scien- 
tific reliability of this report, should render it the authority needed by every 
one who has property to protect and desires to do it so as to secure perfect 
safety. The following extract is in advance of its publication: 

"The science of lightning conductors for the safe protection of property 
and life should keep pace with the science of architecture. The modern 
improvements and progressive changes in the construction of buildings, the 
substitution of metal for wood, the introduction of good conductors into a 
building, the metal water and gas pipes render a plan of protection that 
would have been safe in the days of Franklin totally unsafe at the present 
period. This is one cause why lightning rods occasionally fail. Another 
cause is ignorance, or the desire to save labor in not digging an excavation 
or well down to permanent moisture, and then omitting to put a ground 
plate or an abundance of scrap metal to aid the rod in securing equilibrium 
by the upward movement, in the rod, of the opposite terrestrial electricity. 



LIGHTNING RODS. 27 

For the rod conducts the upward movement of electricity the same as a 
green tree in the spring conducts the upward movement of sap. Again, 
neglecting to make a complete circuit with the lightning rod and arranging 
it so that not even a single point can be struck without having at least two 
outlets for the opposite electricities to unite and secure equilibrium, is the 
cause of an occasional failure. Sometimes well meaning persons start in the 
lightning rod business ; they imitate past workmanship, put up several of the 
best solid platina-tipped points, have but one run down, and save rod by 
using only a foot or two in dry earth, or nearly dry earth. Then they 
marvel because the lightning leaves the rod and sets the building on fire. 
When the definite latent laws of electricity are complied with the lightning 
rod never fails. As there is a definite and wonderful law in perpetual action, 
between evaporation and the fall of rain or snow, to make the annual equi- 
librium of moisture about the same ; so a similar definite but transcendently 
more marvelous action pertains to the equilibrium of the invisible but all 
powerful terrestrial and atmospheric forces of nature. Electric neutraliza- 
tion is maintained by the conductivity of the entire vegetable kingdom. 
Hence the supreme metallic conductor of suitable size, scientifically erected 
and kept in repair, secures certain safety from all damage by lightning to the 
building and its occupants. The perfect lightning rod insures safety from 
Hghtning as the perfect roof insures security from rain. In 1822 the French 
government applied to the Academy of Sciences for the most perfect system 
of lightning rods. After a series of meetings and the most careful delibera- 
tion a report was made by this most eminent body of scientific men in the 
world. The French government immediately issued an order to have all of 
the public buildings throughout the empire protected against lightning ac- 
cording to the plan recommended. A committee from the same body of 
eminent philosophers reported again at the request of the government, in 
1854, in 1855, and finally in 1867. The result of all of their examinations 
and deliberations was, that lightning rods of sufficient size (copper, f-inch, or 
galvanized iron, |-inch), properly made, scientifically erected, connected 
with the subterranean water bed, and kept in repair, are always a certain and 
infallible protection against lightning." 

There are many forms and variations of rod section and of connections. 
Some of these are got up merely to suit the whims of the seller or purchaser. 
Some of them are founded upon correct, and some upon doubtful scientific 
principles ; and some, while said to possess superior virtues over their fellows, 
are, in fact, not so good. 

The materials employed are galvanized wrought iron and copper. Of 
these two, the latter is the best conducting material. In section they 
are best star-shaped and solid. These are only the more simple forms. 
There are many combinations which there is no room to present here. From 
the catalogue of Reyburn, Hunter «S: Co. (North American Lightning Rod 
Company, 494 St. John street, Philadelphia), we select for mention some of 
the many styles. We believe that this firm is the largest manufacturer 
of lightning rods and attachments in the United States, if not in the world- 
Galvanized rods, star-shaped, should be connected with copper socket 



28 MILL CONSTRUCTION. 

couplings in which a female screw engages with corresponding male screws 
on the ends of the sections of rod. The patent star, galvanized rod, f-inch 
diameter, is large enough for ordinary buildings, and is the size generally- 
used. A |-inch rod of this style is used for chimneys, stables, and large, high 
buildings. These rods should be galvanized with the best Silesian spelter, in 
order to preserve a bright surface. Galvanizing is necessary to prevent 
corrosion and consequent loss of conductivity. The patent star copper 
section is made of wrought iron, also galvanized, and covered with sheet 
copper, and then both are twisted. The Phelps patent cable is composed of 
a centre or core of four copper wires twisted together and surrounded by six 
galvanized iron wires. One variation of it substitutes galvanized iron wire 
for the centre. The Cushman patent cable consists of four No. 8 galvanized 
iron wires and four copper wires, all twisted together. Another form is made 
by placing five wires, plain or galvanized, round a large centre wire and 
covering all with sheet copper — the cable being twisted into star shape. In 
the Munn patent cable, four iron wires are covered with sheet copper, 
the whole being twisted, drawing the two edges of the copper wire between 
the wires. The copper wire cable rod is composed of twenty-eight strands 
of copper wire, or of four No. 9 and four No. 16, or seven large wires. 
Cables are continuous ; hence there is no risk from imperfect fittings. The 
vertical points should be held up by three-legged galvanized braces. The 
|-inch solid cojiper star rod is an excellent and durable conductor. 

Paints. — The principal materials used in painting about mills are oxides 
of metals, ground in raw or boiled linseed oil, and silicious paints, which are 
either oxides ground in silicate of potash (water glass), or silica ground in 
oil. The leads, ground in oil, are generally sold in kegs of 25, 50 and 100 
pounds' capacity, requiring to be thinned before using. The thinning 
mediums most generally employed are linseed oil and turpentine. Linseed 
oil is used either raw (unboiled), or boiled. When raw oil is used, driers are 
a necessity. The best driers are powdered litharge, Japan varnish, sugar of 
lead, sulphate of zmc, and turpentine. Turpentine is not, strictly speaking, 
a drier, but by its rapid evaporation causes the paint to harden more rapidly.* 
Japan varnish and litharge, are the most common. To every ten pounds of 
keg paint half a fluid ounce of varnish or half an ounce of litharge is added. 
Care should be taken in employing varnish as a drier not to use more than 

*OiI or spirit of turpentine is generally supposed to be a drier, and is used as such, while in 
fact it is only a thinner and has no drj'ing properties in itself. This has been repeatedly proved in 
various ways, but the following simple experiment will suffice : In two vessels of equal size and 
shape put equal quantities of linseed oil, and with one mix a quantity of turpentine. Allow both to 
be exposed to the same atmospheric influences and watch them. Very soon you will find the quantity 
in each vessel to be alike, showing that the turpentine has entirely evaporated ; after which, if you 
can perceive any difference in the rapidity of the drying between the two, it will be in favor of what 
was originally the pure oil. When a mixture of linseed oil and spirit of turpentine is spread out 
over a surface, the effect is produced which has led so many to call turpentine a drier. The turpen- 
tine rapidly flies off, and the oil is left in a much thinner body than if it had been applied pure, and 
the air has so much the better chance to operate on it, but the turpentine has left nothing behind to 
aid the hardening or drying process. Painters like to use it because it makes the paint flow more 
readily, work easier and spread out better. For inside work it is desirable, because as the rule the 
object is to apply to the surface covered as little oil in proportion to the pigment used, as possible, 
while for outside work the reverse is the case. Turpentine and benzine are almost identical in their 
mode of action, the benzine being the more volatile and escaping more quickly. Neither should be 
used for the outside of a house ; but for the inside they answer not only the purpose spoken of above, 
but, as they evaporate, a "flat" surface, as it is technically called, is formed, and this is generally 
more highly esteemed. 



PAINTS—FIRE-PROOF CONSTRUCTION. 29 

stated, as it makes the paint brittle and causes cracks. No drier is 
necessary if boiled oil is used, as in the process of boiling from one to 
one and one-half pounds of litharge are added. The oil should be boiled 
for about an hour and a half, stirring the while, to prevent the litharge 
from settling. Turpentine is a good medium for thinning, as, while 
causing the paint to flow well and cover evenly, it assists in drying. 
It decreases discoloration in closed rooms, is less costly than oil, and 
when used in the last coat produces a dead surface which is very 
pleasing. As it lacks firmness, it is not so good for outside work as 
paint thinned with boiled oil. To make a good job of painting, the work 
should be free from dust and dirt; all knots should be treated to a coat or 
two of shellac or of white lead, mixed with glue size, to prevent their showing 
through, &c. Holes and irregularities of surface should not be puttied until 
after the first coat, as the unpainted wood absorbs the oil, causing the putty 
to shrink and fall out. Inside work requires from three to four coats, and 
outside from four to six. Ten pounds of keg paint thinned with three or 
four pints of oil will cover twenty square yards of first coat, thirty square 
yards of second coat, forty square yards of third, fourth or fifth coats, &c. 
Brushes should be cleaned with tufpentine and oil if they are to be put away 
— or allowed to stand in water if they will be in demand in a day or so. For 
painting metals the best paints are oxides of iron, red and yellow ochres, and 
red lead, and for galvanized iron (so called) Spanish brown. 

Fire-Proof Construction. — There are three principles on which we 
rely for protection from fire: i. Careful attention to the use of lights and 
disposition of fire-generating materials, such as matches, etc.; 2. Suitable 
extinguishers and well organized fire departments ; 3. Fire-proof construc- 
tion ; or, in other words, (i) Care, (2) Extinguishment, (3) Prevention. 
Fire-proof construction has for some time claimed the attention of architects 
and builders. With such examples of the inefficiency of fire departments as 
we have seen in the great fires of the last ten years, the natural stimulus has 
been toward a protection which would not allow a fire to reach such dimen- 
sions with so little warning. To accomplish this desired result various 
cements and mixtures of different kinds have been tried as filling between 
walls, floors, etc.; but being found insufficient, a more thorough protective 
medium was searched for. Finally the hollow brick was adopted as that 
which most nearly filled the requirements. Bricks are, in themselves, very 
good building material — their walls remaining intact under great heat long 
after iron buildings have fallen in misshapen molten masses, or granite has 
been split, cracked and reduced to splinters. If now this non-conductive 
material is made hollow, inclosing a volume of air, its non-conductibility is 
greatly increased. Hollow bricks now on the market are made either of the 
ordinary brick clay or of terra cotta, fire brick, such as is used in stove 
lining, concrete blocks made of hydraulic lime of Teil, mixtures of plaster of 
paris and ashes, etc. Plaster of paris mixtures are objectionable from their 
liability to crumble with great heat. Clays of different kinds, and concrete, 
are found to answer best, having a high melting point ; besides which they do 
not readily crumble or crack. Where buildings are constructed with fire- 



30 MILL CONSTRUCTION. 

proof walls, floors, etc., every room is in itself a miniature fire-proof build- 
ing. In the use of iron for beams, girders, etc., they should be protected in 
every case, as far as possible, with non-conductive material. Hollow bricks 
are made in various sections. They are made with edges of different angles, 
so that a number of them put together will form an arch, which may be 
either flat or segmental, depending on the sections used. They are much 
lighter than the ordinary brick— a point of merit in their use for fire-proof 
flooring. The difference in weight between a solid brick floor and one of 
hollow fire-proof bricks is largely in favor of the latter.* Where a floor has 
to sustain a load it is necessary that it be as light as possible with the 
required capacity for resisting strain. Arches may be made either altogether 
of hollow bricks or in part, just as required. In cases of hybrid arches, the 
province of hollow bricks is that of lessening the load. Where segmental 
arches are used in flooring, the floor is built tangent to the crown of the arch. 
If a segmental ceiling to the rooms immediately below is undesirable, a false 
ceiling of hollow bricks is built on angle iron bars forming chords to the 
span, these being placed eighteen inches apart and fastened by iron clamps 
to the lower flanges of the girders. Jn flat arches the sections are such that 
the joints radiate from a centre, as do segmental arches. The masonry in 
these arches extends in every case below the flange of the iron beams on 
which they rest. This extension is carefully covered with cement, leavmg 
no exposed joint which flame might attack. The voiissoirs and skewbacks 
correspond in section to the beams on which they rest. Mansard roofs may 
be built of hollow bricks without being the eyesore to the insurance com- 
panies that they are when built in the ordinary way. Partitions built of 
hollow brick are much less expensive than other fire-proof partitions, doing 
away entirely with lath, plaster and furring. Iron, encased in, say, two and a 
half inches of fire-resisting material, is secure. In the form of sectional 
pipe, hollow bricks are employed as a covering for iron columns, tubular 
beams, etc. The fire-proof covering is held to the columns by countersunk 
plates. They are also used as a casing for girders, hollow blocks being 
cemented together for this purpose. To sum up. The advantages of hollow 
bricks are these : Rooms with hollow brick partitions are warmer in wmter 
and cooler in summer than those having partitions made in the ordmary 
way. Floors, partitions, walls, etc., being composed of non-conductive ma- 
terial, and this heat-resisting quality further augmented by inclosed volumes 
of air, are less liable to destruction by fire than built of solid materials. They 
save expense by doing away with furring, lath and plaster in partitions, and 
concrete filling between floors ; they thoroughly and effectively inclose in a 
protective medium the iron work used in construction ; they divide the 
building into fire-proof compartments, thus largely limiting the spread of a 
fire; they produce the general desired result of fire-proofing at a much 
smaller cost than arrived at by any other known method. 

The loss by fire in the Yeager mill, in St. Louis, was four hundred and 
nine thousand three hundred and fifty dollars (!§409,35o). This mill was 

* S?e table on weight of floors. 



FIRES AND THEIR CA USES. 31 

supposed to be fire-proof ; but the system of building and protecting was 
very defective. 

In the new Washburn A mill at Minneapolis, there are upon each floor, 
coiled up for instant use, properly attached to six-inch stand pipes that pass 
up through all the floors at both ends of the building, about one hundred 
feet of rubber hose with nozzles affixed. These are supplemented on each 
fl[oor by numerous chemical extinguishers and barrels of water over which 
are hung red buckets, properly marked and always in place. There is also a 
chemical engine standing in the building. By a system of electric bells and 
speaking tubes any floor can be brought into instant communication with any 
other in the vast building. 

Fires and Their Causes. — According to the fire tables of the 
Insurance Chronicle for the five years ended with 1879, there was reported a 
total of 1,346 flour and grist mills, grain elevators, grain warehouses and feed 
stores burned in the United States and Canada. We place the whole 
together, that the flour and grain risk may be seen at a glance. This number 
made 54 per cent, of the whole number of destructive fires reported. For 
the year, 1879, of flour mills 181 were reported. Of this number, 21 burned 
in January, 24 in February, 14 in March, 13 in April, 15 in May, 12 in June, 
13 in July, 13 in August, 12 in September, 9 in October, 25 in November, 
and ID in December. Of grist mills, 96 were reported burned, as follows : 
12 in January, 4 in February, 9 in March, 13 in April, 7 in May, 8 in June, 6 
in July, 6 in August, 6 in September, 10 in October, 12 in November, 3 
in December. In the year, 1878, 128 flour mills were reported burned in the 
United States and Canada; in 1877, 102 ; in 1876, 87 ; in 1875, 88. In 1878, 
94 grist mills were reported burned; in 1877, 46; in 1876, 38; in 1875, 29. 
It will be seen that, according to the tables given above, destructive fires 
in mills have steadily increased during the last five years ; but this increase is 
probably only apparent. The number of mills has been largely augmented 
in that time, and a greater percentage of fires that occur is reported 
each year, owing to the increased facilities for gathering news. 

As a rule, even in the most modern mills, no provision is made for 
clearing the space between the elevator pulley and the cross or strut board, 
except by taking off, by means of a screw-driver, the entire side of the head ; 
and this, of course, is seldom or never done, unless the belt has parted and it 
is necessary to remove the head to readjust the belt. Many heads are 
so constructed that enough can be easily removed for any adjustment of the 
belt without exposing the space under the pulley at all. In such cases, 
no examination of the fire trap is ever made, and, unless Providence inter- 
venes, at some time the mill will probably go up in smoke, nobody knowing 
how. 

Spontaneous combustion is a cause of many mysterious fires in mills and 
other manufacturing establishments. The peculiarity of fires from such 
sources is, that the exact source cannot be determined ; so that the same 
accident or a similar one is liable to happen at a later time. The dripping 
of oil from a hanger or an over-heated bearing is ordinarily looked upon as 
somewhat of a nuisance and possibly a slight waste; but it may also be a 



32 MILL CONSTRUCTION. 

most dangerous cause of fire. In discussing spontaneous combustion no 
account is to be taken of explosion of mixtures of finely pulverized substances 
and air, such as coal dust, flour and bran, and wool in a state of fine divis- 
ion, etc., but of such substances as have the property of appropriating the 
elements of heat, and storing them, until sufficient temperature is reached to 
ignite the mass. Among such substances are cotton and woolen oil wastes, 
silk, charcoal, lampblack, coal, hay, etc. The spontaneous combustibility 
of bodies may be referred to three sets of causes: i. By spontaneous explo- 
sion of highly combustible mixtures, as gunpowder, nitro-glycerine, etc. 2. 
By direct chemical action, as the combustion of metallic potassium on the 
coming in contact with water. 3. By " eremacausis," or slow combustion, 
as the rotting of a log or ignition of cotton waste. The causes of the effects 
termed spontaneous combustion come under the last two heads. The fact 
that waste (either cotton or wool), saturated with oil, is liable under favor- 
able, and frequently occurring, circumstances to spontaneous ignition, is too 
well established to require any proof. How many times do we read of the 
destruction of cotton mills and machine shops by fire, and " the cause of the 
fire unknown." In such cases the chances are very largely in favor of the 
cause's being that waste soaked with oil or turpentine or varnish has been left 
exposed to the action of the atmosphere, and by the oxidation of the oil has 
stored up sufficient heat for self-ignition, and as a consequence fired the 
building. It has been proved that moisture is very favorable to oxidation, 
increasing the rapidity; therefore, if the waste is kept dry it is in diminished 
danger of ignition. Other things being equal, mineral oils are less liable to 
spontaneous combustion than animal or vegetable; non-drying than drying; 
heavy than light, the reason being, in the latter case, that the flashing points 
and burning points of heavy oils are much higher than light. Silks have been 
known to spontaneously ignite. The late Professor Wise, in his "Through 
the Air," states that he lost several balloons through this property. In these 
examples, doubtless, the varnish was the chief cause. Charcoal and lamp- 
black are both very susceptible to spontaneous combustion. Both possess 
the property of absorbing and retaining gases to a wonderful degree. The 
oxygen is appropriated from the atmosphere and stored within the porous 
mass until a sufficient quantity has been condensed to raise the carbon to 
incandescence. In this absorption of oxygen from the atmosphere, a species 
of natural selection seems to be exerted, by which the nitrogen is refused 
and the oxygen appropriated. As before stated, spontaneous combustion is 
greatly aided by moisture, and in some cases no ignition can be brought 
about without its presence. A drop of moisture on a window pane is often 
sufificient to cause an explosion in a lampblack mill. If a drop of perspira- 
tion or of water falls in a pile of lampblack the moistened portion is instantly 
carried out of the building, for that spot would begin to heat and continue 
until ignition took place, and the little incandescent nucleus would gradually 
extend until the whole place would be on fire. The cause of spontaneous 
combustion of coal has not been so definitely established. It is thought by 
some to be the oxidation and decomposition of iron pyrites, the heat thus 
produced firing the mass. This will not, however, account for all the cases 



FIRES AND THEIR CA USES. 33 

of spontaneous combustion of this article, as coal free from pyrites is quite 
as liable to ignite as " brassy " coal. The real cause is probably the same as 
in the case of charcoal and lampblack, /. e., occlusion of oxygen within its pores. 
In the year 1874, 4 per cent, of all vessels carrying coal were destroyed by 
the spontaneous combustion of their cargoes. The prevention of this has 
been attempted by the expulsion of air from the hold and bunkers by means 
of carbonic acid gas. Farmers are aware of the charring of the interior of a 
haystack when the hay is not properly cured. All cereals are supporters of 
animal parasitic life. These parasites breathe oxygen or give off carbonic 
acid. They thus form mediums for the storing of oxygen. Vegetable 
parasites absorb oxygen in their pores; and both animal and vegetable 
are liable to ferment. If the hay be stacked wet, by a process of budding 
these parasites increase enormously — -constantly increasing the supply of 
oxygen and causing the mass to heat until the interior is charred or the 
whole consumed. If, on the other hand, the hay is thoroughly cured by 
spreading in the sun until the juices of the plant are dried up and all 
parasitic life destroyed, its liability to spontaneous combustion is reduced to 
a minimum. A little pile of middhngs, on which oil drops from a bearing, 
will soon heat and burn. 

Middlings and oil are not alone in their power of generating fire. Damp 
smut or bran will do it. One mill has been told of where fire was caused by 
dampness in the smut room, and another where a bin of bran which 
had been used a long time without having been entirely cleared out gathered 
dampness at the bottom, from which combustion ensued. One mill may run 
for years without any accident without taking any precaution. If it escapes, 
it is only because the atmospheric conditions of an explosion are not 
fulfilled, "more by good luck," etc. Elements of destruction are ever 
present. 

There are few mills where there is sufficient precaution taken against 
sudden explosions and fires ; and sometimes millers are more than ordinarily 
careless. There is one case on record where there was a grist of very dry 
buckwheat being ground at night and run through a muslin bolt kept 
for coarse grain; some black specks in the flour showing a defect in the cloth, 
one of the doors was opened to learn the reason, when the bolt was 
in motion. On taking the candle near the door there was an explosion: 
both dust and silk vanished in a flash, leaving nothing but the bare skeleton 
of the reel. 

Soft coal is peculiarlv liable to spontaneous combustion, especially fine 
coal or culm. If stored, when the least wet or damp, in closed sheds or where 
there is little or no. circulation of air, this danger is increased. There is an 
additional reason for protecting coal from wet ; and that is that it will lose 
much of its heating power if not kept dry, beside emitting gases which are 
noxious to the throat and lungs. A recent circular of the Manufacturers' 
Mutual Insurance Company calls attention to the property which most 
bituminous or soft coals — and some semi-bituminou,s varieties — possess of 
taking fire spontaneously when exposed to moisture, or even dampness, in a 
place without free circulation of air. Aside from the danger of fire, the same 



34 



MILL CONSTRUCTION. 



causes which, when acting strongly, cause spontaneous combustion, are 
likely, when present in a less degree, to give rise to injurious vapors of sul- 
phurous acid, carbonic oxide, and other products. Even with anthracite 
coal, a suffocating effluvium, perhaps of sulphurous acid, is often perceived 
when the contents of the bin are disturbed. 

Artesian Wells. — These are of use in places such as we often find in 
cities where the supply of water in case of fire is drawn from the city mains, 
and is liable to fail in case there is another fire in the neighborhood, and the 
steam fire engines draw from the mains. It would not be very pleasant to 
be left without water in such a case, especially if the roof was of wood and 
the wind in the direction of the mill. In this case an artesian well comes in 
play. 

Tanks. — Tanks for water are best made of cedar wood or of iron, the 
latter either painted or galvanized. Where there is to be a tank of any 
considerable size provision must be made for its support, as water is a very 
heavy article. Many buildings have been badly sagged out of shape by a 
large water tank. A cubic foot of water weighs about 62-|- pounds ; a gallon 
about 8 pounds. The subjoined table gives the contents of tanks, of different 
diameters, in cubic feet and in United States gallons of 231 cubic inches or 
7.4805 gallons to a cubic foot) and for one foot of height of the tank. With 
the figures given the contents of a cylindrical tank, of any height and of the 
various diameters stated, can be found. For tanks of any given height 
multiply the figures given below by the height of the tank in feet. Thus, a 
tank 48 inches in diameter and 5 feet high will contain 62.830 cubic feet, or 
470 legal United States gallons of 231 cubic inches to the gallon. For the 
weight of water multiply the number of cubic feet by 62:^, which will give it 
roughly. 



Inches 
Diameter. 


Cubic Feet. 


Gallons of 231 
Cubic Inches. 


Inches 
Diameter. 


Cubic Feet. 


Gallons of 231 
Cubic Inches. 


24 


3.142 


25.00 


54 


16.904 


118.94 


27 


3,976 


29.74 


60 


19.036 


146.88 


30 


4.909 


36.72 


66 


23.760 


177.72 


33 


5.940 


44-43 


72 


28.276 


271.52 


36 


7.069 


52.88 


78 


33-184 


248.24 


39 


8.296 


62.06 


84 


38.484 


287.88 


42 


9.621 


71.97 


go 


44.180 


330.48 


45 


11.045 


82.62 


96 


50.264 


376.00 


48 


12.566 


94.00 









Pumps. — For fire protection a pump should be put in that can be 
forced to a high capacity and run, without stopping, for a long time. It must 
be remembered that the fire pump of a mill is not always used to put out fire 
in the mill itself, but to protect neighboring buildings, and perhaps a whole 
district. 

Every year the hydrants should be carefully looked after to prevent their 
freezing in the winter. Rotary pumps should be emptied by turning them back- 



WELLS— TANKS— P UMPS— HOSE— RAM. 



35 



wards. All left-hand valves and water gates should be distinctly labeled to 
prevent their being broken by attempts to turn them the wrong way ; as well 
as to save time in case of fire. Every left-hand valve should be plainly 
labeled and marked with an arrow to show the direction in which it should 
be opened ; it is better to remove them entirely and replace them with right- 
handed valves. 

Hose. — Sufficient hose should be provided to meet all possible require- 
ments. All hose should be inspected and tested under fire-pressure at least. 
once every three months ; and it would be better if it was looked to 
each month. The fire hose should never be detached from the stand pipe, 
and never loaned for any trivial purpose. Only first-class hose should 
be purchased. That from the New York Belting and Packing Company, 37 
Park Row, New York, may be recommended. This company manufactures 
an antiseptic test hose which is made under a patented process for preserving 
the hose from mildew or rot. The duck used in the manufacture of this 
hose is made from the very best long staple cotton, making a duck of the 
greatest tensile strength possible to be made. All of the duck used in the 
manufacture of this hose is chemically treated with carbolic acid, supplied 
directly to the duck at a temperature of over 300 degrees of heat, which is 
the only process whereby the fungi or decomposing matter in the duck is 
effectually destroyed. The rubber used in the manufacture of this hose is 
all fine Para, being the strongest and very best rubber known. The ends are 
made extra heavy to resist the greater pressure they are subjected to, and 
capped to prevent air or dampness penetrating the hose. The rubber suction 
hose is made on spiral brass wire, in sizes from f inch up to 2 inches internal 
diameter, and on fiat galvanized iron wound spirally in sizes from 2^ inches 
up to 12 inches. The "smooth bore" suction hose has metal imbedded in 
the rubber, entirely out of sight, so that the interior or bore is perfectly 
smooth. The company also manufactures all other kinds of hose, such as 
"conducting," for leading water under moderate pressure; "hydrant," suit- 
able for hydrants, force pumps, etc.; "engine," for all general purposes 
where a strong, reliable hose is required; "extra heavy steam" and "star 
linen " and " cable " seamless multiple cotton hose. The " star " and " cable 





FiG. I. — New York Belting and Packing Company Hose. 

are rubber lined, and all of the fabric hose is prepared under the antiseptic 
process. 

The Hydraulic Ram. — Where economy of water consumption is not 
considered, hydraulic rams have probably no equal in cheapness of work 
and thoroughness of action. Simplicity, automatism, convenience and low 



86 



MILL CONSTRUCTION. 



price are some of their principal features. For supplying country houses, 
barns, factories, mills, and railway stations, they are much cheaper than 
pumps doing the same work. As ordinarily made, they are capable of 
pumping from half a gallon to eighty gallons per minute, and discharging it 
at a distance up to 150 feet. All that is necessary is plenty of water, with a 
fall of not less than 18 inches, with a drive of not less than 25 feet. This 
length of pipe is necessary to accumulate the required pressure and velocity 
of supply. If space is limited, this length of pipe may be obtained by 
coiling the drive in, say, a six-feet coil. This gives the necessary ramming 
pressure and velocity, and economizes space, as the coil may be placed 
directly under the flume. The drive pipe should be as free as possible from 
elbows or short turns, as these cause friction and loss of power. It should 
also be placed underground to be out of danger from frost and external 
injury. The power of hydraulic rams is directly proportional to the height 
of the falls; and the height to which the water is raised to the height of the 
falls. With a fall of 5 feet, water can be raised to a height of 50 feet; 
and with a fall of 10 feet to a vertical or horizontal distance of 150 
feet. The ratio existing between the water used and the water wasted 
ranges from i : 10 to 1 : 14; or in other words from i-io to 1-14 of the 
water supplied by the drive is utilized, while the remainder is wasted. 
This may seem wasteful for the amount of work done; but, when it is 
calculated what would be the cost to accomplish the same work by 
another machine, such as a wind mill, it will be found to compare 
very favorably with it, or any other machinery, to accomplish this same 
work. It is true that a wind mill requires little ar no attention, but 
it is also true that it will work only when the "spirit moves it," — whereas 
the ram is always ready for work, and automatic in its action, requir- 
ing only that the sluice shall be opened for it, when it will pump until 
stopped. American hydraulic rams are better than European. A good 
American hydraulic ram will discharge, at 100 feet vertical and 100 feet 
horizontal distance, as follows : 



Vertical Distance. 


Horizontal 
Distance. 


Ram 

Number. 


Gallons 
per Minute. 


100 feet. 


100 feet. 


2 


.12 


100 " 


100 " 


3 


•23 


100 " 


100 " 


4 


•49 


100 " 


100 " 


5 


.86 


100 " 


100 " 


6 


1-54 


100 " 


100 " 


7 


3.08 


100 " 


100 " 


8 


7.06 


100 " 


100 " 


9 


15-04 



Such rams are made of cast-iron and brass, with brass valves and valve 
stems; are very durable and inexpensive — a No. 2 costing §9, and a No. 9 
$225. The hydraulic ram is really a French invention — Montgolfier, the 
balloonist, first conceiving the idea. Yet at the Paris Exhibition of 187S, 



RAM—FIRE EXTINGUISHMENT— HEATING. 37 

where American rams were shown in operation, they were viewed with 
suspicion by Frenchmen, they insisting that there must be a concealed pump 
to perform the work done. 

Chemical Extinguisher.— The chemical extinguisher has, of late 
years, taken an advanced position as a fire combating agent. It is of great 
value for the extinction of a fire in closed rooms. It should be frequently 
tested. 

Fixed Water Pipes. — One method of fire extinguishing which is 
largely employed in New England, among the cotton factories, is the system 
of fixed water pipes, extending through every story and extending along all 
the ceilings. This system of pipes is in permanent connection with a power- 
ful force pump, and the ceiling pipes have their sides and underneath por- 
tions perforated with fine holes, which makes them act as very thorough 
sprinklers. Over these holes thin tissue paper should be parted in order to 
prevent their clogging with dust. Each story should have its own pipes; and 
if possible those of each story should be painted of a special color, in order 
to distinguish it from those of other stories. Each pipe should have its valve 
properly labeled and numbered, so that when the pump is put in action any 
desired story may be at once subjected to a thorough drenching, directly the 
fire signal is given by electric bell, speaking tube, or other alarm. Water 
pipes should have as few bends as possible, and they must not be run where 
they are liable to freeze. 

Steam. Pipes. — Steam is an excellent extinguisher where there is a 
confined place in which to act. In that case it is a sure suppressor of com- 
bustion. The steam extinguishing system costs little to fit up, nothing to 
maintain when not in use, takes up little space, is always present and quickly 
available. 

Heating. — The method of heating most commonly employed, especially 
in steam mills, is by steam pipes, either in straight lines or in coils — although 
these last are frequently superseded in the best and largest mills by radiators 
made of cast or wrought iron or of short lengths of straight pipe. Heating 
by steam has the advantage that it is easily controlled, and the disadvantage 
that unless it is well controlled the temperature is apt to rapidly vary beyond 
the limits of endurance or at least of comfort. Steam pipes have the 
advantage that they take up little room. They can be readily put in 
buildings that were not intended to have them, are less trouble than stoves, and 
are more readily controlled. The Boston Manufacturers' Mutual Fire 
Insurance Company recommends overhead heating pipes, because one of the 
greatest dangers to which they are exposed and one of the heaviest causes 
of loss are the collection of combustible material on steam pipes where 
they are ordinarily placed at the sides of the room under the windows. One 
of the most frequent faults reported by their inspectors is "Combustible 
matter on steam pipes." There is, aside from insurance considerations, less 
liability to breakage. 

There is no fixed rule which can be laid down about how many square 
feet of heating surface, or how many pounds' pressure will be needed 
for each and every building. The kind of building and its location are 



38 MILL CONSTRUCTIOX. 

important factors in the calculation. Thus, wooden buildings need more 
pipe or more pressure than stone, and stone more than brick. Those with 
iron fronts need still more (other things being equal), and those that 
have the fronts largely in glass take most of all. The number of cubic feet 
of space heated by one horse-power of steam is approximately as follows : 

Brick dwellings, in blocks, as in cities, . . 20,000 cubic feet. 

Brick stores, in blocks, as in cities, . . 15,000 " " 

Brick dwellings, exposed all round, . . 15,000 " " 

Brick mills, shops, factories, etc., . . 10,000 " " 

Wooden dwellings, exposed, .... 10,000 " " 

Foundries and wooden shops, . . . 8,000 " " 

Exhibition buildings, largely glass, etc., . . 5,000 " " 

Each horse-power of a boiler will supply about 300 feet of i-inch steam 
pipe, or 100 square feet of heating surface for direct radiation, and for 
indirect radiation 420 feet of pipe or 140 square feet of surface. Doubling 
the diameter renders it necessary to add 30 per cent, to the surface ; and, 
trebling the diameter, 30 per cent, is required. 

Liigllting. — A liberal allowance of light is desirable in every mill. 
There are some locations where it is next to impossible to get it without 
resorting to some special contrivance. When there are neighboring build- 
ings that are very near or very high, inclined reflectors may be used similar 
to those employed in cities, and which will throw inside of the buildings the 
light which comes from above. If the faces of the windows are made flush 
with the outer surface of the wall more light reaches the interior than if, as 
is generally the case, they are set back a few inches. Sashes should be made 
preferably of iron, as being more nearly fire-proof than wood; and fire is a 
thing that almost every mill must look forward to as bound to come sooner 
or later. The French style of windows, hinged at the side, is well adapted 
to flour mills, if the sashes open outward, so that in case of explosion they 
will readily yield to the outward force, and thus save some of the damage to 
if e and property within.* 

The methods of artificial lighting are by candles, lamps, fixed illuminating 
gas, carbureted air and the electric light. The candle is one of the most 
common sources of fires, and the lamp is about as bad. If lamps are used 
no oil should be burned that "flashes" at less than 110° F. The gas 
machine, commonly so called, does not generate illuminating gas, but aft'ords 
a supply of atmospheric air, saturated to a greater or less degree with hydro- 
carbon vapor. The difference between vapor and gas is that the gas is in 
a permanently gaseous condition, while a vapor is only temporarily so and 
liable to condense again into liquid form with time or lowering of tempera- 
ture. Still there are many cases where large mills could do better by making 
their own gas than by buying it from the city or the gas company. The 
Seneca Lake Mills, Watkins, N. Y., are lighted by the electric light. 

* Suggested by Mr. Louis C. Madeira, Philadelphia. 



LIGHTING— ESTIM A TES. 



39 



Estimates. — Comparatively few persons appreciate the importance, in 
asking for estimates, of being explicit, so that manufacturers, millwrights or 
builders may have a clear understanding as to just what is wanted. For 
instance, a letter is sent asking for an estimate on " a three-run mill," or 
"an engine and boiler," or "bottom figures on a turbine wheel," etc. No 
one could reply intelligently to such inquiries. "A three-run mill " does not 
say what is wanted, as one three-run mill may cost $2,000 more than another; 
an engine may be 5 horse-powers, or it maybe 100 horse-powers, and turbine 
wheels are built from ten inches to six feet in diameter. A correct estimate 
depends upon the size, capacity, make, power, materials, finish, etc. 

If, in asking for estimates or ordering machinery, the following rules 
are observed (as far as is practicable), much correspondence and many 
misunderstandings may be avoided, and all parties concerned will have a 
clear conception of just what is wanted: 

I. AVhere an estimate is wanted for a new mill, give — 



The number and size of buhrs (or capacity) 
wanted. 

A full description of location, on level 
ground or side hill; its relation to 
road, railwa}^ and power ; where it 
is most convenient to receive grist 
work, and where merchant grain. 

If a basement is attainable. 

2. If you have a building, give — 

Size of sills. 

Height of basement, if there is one. 

Height of each story (measuring from top 

of floor to top of next floor). 
Height of attic in centre and on sides. 
Which way the comb of the building 

runs. 



Relative position of site to railroads, 

streets, etc. 
Place to receive grain. 
Location of water wheels or engine. 
If a " merchant " or " custom " mill. 
Old or new process, or straight grade. 
Whether )'0u will grind grist, or exchange. 
Send sketch, with any suggestions 3'ou 

may wish to offer. 



Position of girders in building, with di- 
mensions. 

Depth of joists on each floor. 

Are joists set on girders or gained in even? 

Number of posts through the building, 
and if possible send sketch with full 
dimensions. 



3. If you expect to use water power, give — 



Head and fall, and number of cubic feet 

per minute.* 
Distance from top of headwater to buhr 

floor of building, or to top of ground. 
If )'ou have a turbine, state what make, 

4. If you want an engine, give — 

Diameter of C3'linder and length of stroke. 

Size of boiler. 

Kind of pumps, etc. 

Or, if you wish a person consulted to 

5. If you have an engine, give — 

Kind of engine; builder. 

Diameter of cylinder and length of stroke. 

Length of main shaft from centre of bed 

to end. 
If it runs over or under, that is, whether 

top of band-wheel runs to or from the 

cylinder. 
Diameter and face of fly wheel. 
Diameter and face of main band-wheel if 

the fly wheel is not belted. 



size, etc., and how it runs (with or 
against sun), revolutions per minute, 
etc. 
If )'0u want a turbine, give size, and kind, 
and location. 



decide as to engine, state what it is to 
do, or the amount of work it is ex- 
pected to perform. (In ordering wa- 
ter-wheels observe the same rule.) 



Diameter of overhang and length in full 
detail. 

Number of revolutions per minute. 

Send sketch with all measurements noted, 
showing location of the engine with 
regard to the building; location of 
well or tank, and show by arrow 
which way the engine runs. 



* See " Measurement of water power.' 



40 MILL CONSTRUCTION. 



6. In ordering: buhrs, state — 

How thej- are to run (watchwise or re- 
verse).* 
What they are to grind. 

7. In ordering mill spindles, give- 
Distance from face of bedstone to the wood 

bridgetree on which the step is set. 



With or without balance boxes. 
Size of eye in runner and bedstone. 
If drive irons are wanted. 



Diameter of spindle, etc. 

Be particular in giving all dimensions. 



8. In ordering pulleys or gearing to go on old shafting, give- 



Exact size of bore. (If possible always 

send a wire.) 
Size of key seat, or if set screw is 

wanted. 



Name the place to which machinery is to 
be shipped and, if thought best, by 
what route. Give name and P. O. 
address plainly and in full. 



Observe the foregoing and always be explicit. Do not fear being too 
particular. If possible, however, we would advise you to visit the works 
with which you are treating. 



* Most makers will send buhrs or any machinery running watchwise, if not otherwise ordered. 



^*^ 



CHAPTER II. 

MILL PLANS. 

Roller and Buhr Mills— New Process Buhr Mill— Three-Run Mill— Two-Run Low Grinding Mill- 
Niagara Falls Mill— Burned Yaeger Mill— Deseronto Mill — Five-Run Buhr Mill— Two-Run 
Buhr Mill— Jlill Office— Seven-Run Mill— Oliver Evans' Mill. 

'Roller and Buhr Mills. — As regards the building itself, no difference 
need be made in size or arrangement between a roller and a stone mill. The 
building for a 450-barrel roller mill may be about 46 by 68 feet on the ground, 
and four stories high, with a basement. The basement may be 10 feet high, 
the milling floor 12 or 14 feet, the next two, 16 feet each, for the bolting and 
the purifying. There may be an attic for the elevator heads and such like. 
If it is a steam mill, the engine and boiler should be in a separate building. 
For making 450 barrels of flour per day of 24 hours there will need to be a 
200 horse-power engine or turbine. The main driving-shaft should be in the 
basement, and be a 3 or t,^ inch line, making 300 revolutions per minute. 
Immediately above this put the platform for the rolls, of which there must 
be ten pairs. The shafting on the upper floors may be driven either by 
an upright shaft taking motion from this main line, or by belts, — as may 
be convenient. On the first floor place ten sets of rolls, five sets of 30-inch 
under-running stones, and three flour packers. The bran packers may 
be either on the first floor or in the basement, as may be preferred. The 
next two floors should be taken up by the bolts and the purifiers, the chests 
extending up through the two floors, and the purifiers about equally divided. 
There may be three chests containing eighteen reels, each 18 feet long and 
32 inches diameter, and making 22 to 26 revolutions per minute ; or these 
reels may be put in four chests. There will need to be nine purifiers 
of medium size, say four on the second floor and five on the third. This 
number of purifiers will handle the largest quantity of middlings that can be 
made. 

The cleaning machinery may consist of one side-shake separator, two 
brush machines, and a rolling screen. If there is much cockle there will 
need to be a cockle machine. This takes care of garlic also — a great 
nuisance in Pennsylvania. The scourer may be omitted, as the brush 
machine will do the work better and leave the enamel of the bran in a more 
nearly perfect state. The cleaning should be done in the basement if 
possible, so that it may be readily inspected from time to time. For 
this purpose, the basement must be well lighted and dry. The rolling screen 



42 MILL PLANS. 

and cockle machine might be placed above, or the material could be 
nm first into the separator, then into the rolling screen, then into the cockle 
machine, then to the brush, running first down and then up. On the 
first floor a i-inch over-head shaft will be required to drive the packers. 
There should be one line of 3-inch shafting for the bolts, starting at the 
head, and making 40 revolutions. On the third floor the purifiers should be 
driven from counters from the 3-inch shaft. This counter shafting should 
be 2\ inches diameter, and the purifiers will have to be driven, say, 500 
revolutions. On the fourth floor put up one line of shafting 2 inches in 
diameter, driving the elevators. The bran duster may be placed on the 
second or on the third floor. There should be one heater for each two pairs 
of rolls. The scalping reels must go in the basement, just under the first 
floor and under the rolls. These will all be driven from one shaft, 2 inches 
in diameter, making 20 revolutions. The scratch rolls could either be driven 
from the horizontal shafts above, or all be geared from the shaft that drives 
the rolls below. Probably they would be best geared from the roll .shaft. 

The smallest roller mill that can be profitably put up will be about a 
125-barrel mill, with 9x18 rolls. A 450-barrel buhr mill should have eleven 
sets of 4-foot stones, making 160 revolutions, for wheat, and five sets for 
middlings. These wheat stones would take eight bushels per hour each, and 
should make about 45 per cent, of middlings. 

New Process Bulir Mill (Abernathy). — For a ten-run mill there 
may be a building 60 by 70 feet on the ground, four stories high, with a base- 
ment — this last being at least 12 feet high. The next stories should be 
respectively 14, 18, 18, 17 feet high in the clear. In the basement at one 
end there should be the husk frame of iron or wood. Parallel with this, and 
16 feet from it, there should be a line of 3 or 3^ inch shafting firmly 
mounted, running through the outer wall to the motor. From this run reel 
belts, one for each run of stones, to the stone spindles. 

Three-Run Mill. — Figure 2 gives an end and side elevation, and Fig. 3 
basement and attic plans, of a three-run mill designed by E. P. Allis & Co., 
and intended to make from two and a half to three barrels of flour per hour 
with 36 horse-powers, with an automatic cut-off engine of good construction, 
and a boiler efficiency of nine pounds of water to one of coal. The con- 
sumption of fuel per hour should be 108 pounds of steaming coal, or 0.085 
cord of mixed wood. 

Two-Kun Low Grinding Mill (Allis). — "The driving power of 
this mill, Figs. 4 and 5, is a 10 x 30 automatic cut-off engine, making 90 
revolutions per minute. The power required is about 25 horse-powers, 
although the engines will easily give 10 horse-powers more. In running the 
mill for ten hours the fuel required will be about 750 pounds of steam coal or 
about one-half cord of good wood. Water power can be used to drive this mill 
in place of the engine where required. The mill consists of two runs of 48- 
inch old stock French buhr millstones, one used for grinding wheat and the 
other for grinding corn and feed. The stones are driven by a one-quarter turn 
belt from the line shaft, and either may be stopped or started without stopping 
the engine. The stones rest on a wooden hurst frame, and are covered by 




I: 







Pi 
I 

s 



o 



< 

CO 



o 



3 
PO 






< 











< 



TWO-RUN LOW CjRJNDING MILL {ALLIS). 47 

walnut finished curbs, the wheat stone having a silent feeder and the feed 
stone a hopper, shoe and damson. The spindles are of cast-iron, cast on 
end, and the trampots what are known as copper-lined top lift. The bolts, 
elevators and smutter are driven from an upright shaft, which is geared 
to the line shaft in basement by bevel mortise or core gears and pinion with 
dressed teeth. This shaft rests on a heavy steel step and is supported at 
each floor by boxes. The main line shaft in the basement is coupled direct to 
the engine shaft, and is supported on a line of posts by bracket boxes. The 
smut and separating machine stands on top of the stock hopper on the 
second floor. The bolting chest stands on the second floor and contains two 
reels 32 inches in diameter and 18 feet long, with double conveyors under 
each reel, and is driven by an upright shaft and mitre gear from the line 
shaft in the attic. There are four elevators in the mill. The wheat is 
taken in the wheat hopper on the grinding floor and passed into the foot of 
the wheat elevator, which takes it up into the attic and spouts it into the 
smut and separating machine, from which it passes direct into the stock 
hopper over the wheat stone. The meal from the wheat stone is spouted 
into an elevator and taken to the bolts. The corn or feed is taken into 
a hopper on the grinding floor and elevated into the stock hopper over the 
feed stone, and the ground feed is ele\'ated into a feed bin on the second 
floor, from which it can be drawn at pleasure. With the addition at any 
time of another one-half chest of bolts, a middlings purifier, a set of porce- 
lain rolls to grind the middlings, and a set of smooth chilled iron rolls for 
extracting germs, this can be made a high grinding new process mill. The 
power provided is amply sufficient. A few more elevators would be required 
and the change could be made very easily." 

The Niagara Falls Mill. — Fig. 6 is one of the finest mills in 
the country, both in point of design and convenience, in the substantial 
character of the building and machinery, and in the high finish and ex- 
cellence of the workmanship. The plans were made by E. P. AUis & Co. 
in the fall of 1877, and in January, 1878, the entire contract was awarded to 
them. They furnished the entire machinery and superintended the erec- 
tion of the mill and power, turning it over to the owners, Schoellkopf & 
Mathews, of Buffalo, N. Y., in September of that year, in complete running 
order. 

The mill and elevator are situated on the brink of that immense canon, 
nine miles long, which Niagara has worn out of the solid rock in the lapse of 
centuries, and whose depth at the mill is 310 feet. The location is some- 
thing over half a mile from the Falls, and at the end of that expensive canal, 
only a mile long, which taps Niagara River above the Rapids and Falls. 
The head race is about 300 feet long, the sides being built of dressed stone 
laid in cement, and is arched the greater part of its length. There are two 
head-gates, one at the pond and the other at the bulkhead. This last is 
made of cut stone and is 18 feet square, and deep enough to hold 15 feet of 
water. Both raceway and bulkhead were made deep enough to stand over 
two feet of ice without drawing upon the head. From the bulkhead the water 
is brought to the water-wheels, a distance of 58 feet, in a tube made of boiler 



48 



MILL PLANS. 



iron and lo feet in diameter, the water leaving the tube at right angles with 
the head race. The pit in which the water-wheels are placed was blasted 
out of solid rock on the edge of the precipice. It is 50 feet deep, 34 feet 
wide and extends back 30 feet. The motive power is furnished by two 
turbines. The pit under the larger wheel is 7 feet deep and 9 feet wide, 
and that under the smaller wheel is 7 feet deep and 6 feet wide. The pen- 
stocks of both wheels are placed on iron girders, supported by heavy iron 
columns. The larger turbine is 54 inches in diameter, and is placed in an 
iron penstock. Under a head of 52 feet it gives 660 horse-powers, which is 
said to be the greatest power furnished by any wheel west of Lowell, and 
was at that time the greatest power supplied to any flour mill in the world by 




Fig. 6.— NiAGAR-iv Falls Mill. 

a' single wheel. It is calculated that the power it supplies would drive a 
forty-run "new process" mill, with all of the necessary machinery. The 
shaft for the wheel is of steel, and is 53 feet long and 5 inches in diameter. 
This wheel drives the mill proper and all of its machinery except the flour 
packers. These and the cleaning machinery, together with the elevator 
machinery, are driven by a 36-inch turbine in an iron penstock, which, under 
the same head as the larger wheel, develops about 300 horse-powers. The 
shaft for this wheel is also of steel, 3-2- inches in diameter, and of the same 
length as the shaft from the larger wheel. Both wheels are regulated by 
water-wheel governors. The upright shafts of both wheels are carried on 
wrought iron "I" beams, 36 feet in length, and fastened at either end to 
heavy cast brackets, which are firmly bolted to the sides of the pit. The 
driving wheels and line shaft are carried in cast-iron bridgetrees, which are 
supported by three wrought-iron "I" beams placed across the top of the 



THE NIAGARA FALLS MILL. 



49 



pit. It will be seen that everything, except the head gates, connected with 
the carrying and utilizing of the power is built of iron or stone. We have 
thus enlarged upon this branch of the subject, not only because it is one of 
the most interesting points in connection with the mill, but also because it is 
one of the most expensive applications of water power in the world. The 
present edifice is only the beginning of a series of manufacturing establish- 




FiG. 7.— Sectional End View of Niagara Falls Mill. 

ments which will make Niagara famous as an industrial centre. The canal, 
where the power becomes most conveniently serviceable, is only about 200 
feet from the river, and there is room right there for thirty mills, each with a 
hundred feet front, and each driven by a practically unlimited water power. 
Moreover, this power may be used all the time. In winter the Rapids cause 
a kind of granulated ice which clogs the wheels of the paper mill at Goat 
Island. This is not the case with the power supplied to the Niagara Falls 
Mill. Ice may form in the canal two or three feet thick, and yet an ample 
supply of water will run under the ice as long as Lake Erie remains where it is. 



50 MILL PLANS. 

Let us now glance at the mill building and elevator, accurately repre- 
sented in the engraving, Fig. 8, but the imposing appearance of which can only 
be appreciated by actually seeing it and taking in the ensemble of the situa- 
tion. The material used in construction was Niagara limestone, quarried 
from the basement and wheel pit, and the walls are 4-^ feet thick. The main 
building is 130 feet long, 65 feet wide and 108 feet high. There are six 
stories, of which the first, third and fifth are 16 feet high ; the second, fourth 
and attic, 14 feet high, and the sixth story, 10 feet high. The roof covering 
the structure is iron. The mill is planned for thirty-two runs of 4-|-foot buhrs, 
and has at present twenty-two runs in operation. The buhrs stand in two 
lines of eleven pairs each, the main line shaft running between these lines. 
The shaft is supported on an adjustable cast-iron stand. The buhrs are 
driven by quarter-twist belts and are placed on solid iron hursts. On the 
stone floor there are six flour packers and a very nicely furnished office. A 
more definite idea of the arrangement of this floor and the other parts 
of the mill and elevator can be obtained by consulting the sectional views. 

The third floor contains six sets of Wegmann's porcelain rollers and four 
sets of chilled iron rollers, the wheat garners, the flour bins over the packers, 
the bran bins and three two-reeled bolting chests for dusting middlings. 
The fourth and fifth floors contain the bolting chests, in which there 
are forty reels, four large-sized bran dusters, fourteen purifiers and the 
exhaust fans from the stones. On the sixth floor are the gearings to 
drive the bolts, heads of elevators, aspirators, first dust room from purifiers, 
etc. The attic contains two reels, machinery to drive the passenger elevator 
that runs from the top to the bottom of the mill, dust rooms, etc. 

The elevator and cleaning rooms connected with the mill are 132 feet 
long, 40 feet wide, and have a total height of 88 feet. The elevator is divided 
into twenty bins, each holding 6,500 bushels, and, therefore, has a capacity 
of 130,000 bushels, although more can be crowded into it. The basement is 
built of stone and the rest of the building of " Lamire " walls, covered with 
corrugated iron. The cleaning rooms are in the elevator building and next 
to the mill. The machinery is arranged in sets of four machines on 
each floor, and consists of two large brush machines, four smutters, five 
separators, two cockle separators and a large suction fan. Between the mill 
and elevator is an archway 30 feet wide, with two railroad tracks and a 
wagon track running through it. These tracks are provided with a transfer 
table, so that cars may be changed from one track to the other, and switched 
without employing an engine, as the transfer table connects with the power 
that drives the elevator. Under the table there is a large track scale. The 
space above the tracks is used for storing bran and offal, which may be 
drawn directly into the cars. 

The mill and its accompaniments were constructed with a view to their 
efficiency and not of their cost to the proprietors. The mill contains every 
appliance of a first-class modern "new process" mill, and has a capacity of 
about 1,000 barrels per day, and employs about twenty-five men. In 
connection with the mill, but in separate buildings, are the cooper shops 
and warerooms. Machinery is used for making the barrels, the power being 
transmitted to the cooper shop from the main building by wire rope. 



NIAGARA FALLS MILL. 



53 



Fig. 9 shows in detail the wheel pit, turbines, iron flumes, the steel 
shafting, main driving gear and iron bridgetree supporting the same and 
regulator, forming the magnificent power of the Niagara Falls mill just 
described. This is perhaps the finest water power in the world, and was 
designed and built expressly for that mill. 




o 

h 



< 



Z 
I 






< 

I 



< 



o 



Figs. 10 and ii are made from photographs taken in the Niagara Falls 
mill, and show the packers and one line of eleven runs of 4-^-foot stones. 
The finish of the top of hurst frame, the curbs, silent feeders, lighter screws, 
etc., is first class. 



54 



MILL PLANS. 



The "Excelsior Mill" Minneapolis, Minn. — This mill was 
designed and built in 1877, by E. P. Allis & Co. for the Hon. D. Morrison, 
of Minneapolis, who leased it to C. A. Pillsbury & Co., by whom it is now 




< 






run. It had originally thirteen runs of 48-inch violet millstones, set on an 
iron hurst frame and driven by. a quarter-turn belt from the main line shaft. 
This shaft was driven direct from the water-wheel by a large bevel mortise 



THE " EXCELSIOR MILL. 



55 



wheel and pinion. A large belt from the main line shaft drives a line of 
shafting in the fifth story of the mill, and from this all the bolts, elevators 
and purifiers are driven. There were twenty-three reels in the mill and ten 



D n 



D 



D a 



D 



□ □DO 

O Q 

D □□ 



a 



% 



a D 



□ 



XL 



D ;n=; 



G 



a D 



X 



o 
03 



purifiers, the middlings being properly graded on to the latter. In the ac- 
companying diagrams Fig. 12 shows the plan of the basement, Fig. 13 the 



56 



MILL PLANS. 



plan of the bolting floor, Fig. 14 the attic plan, Fig. 15 a sectional side view 
and Fig. 16 a sectional end view of this mill. 

The builders completely remodeled this mill in 1879, taking out 11 runs 




(- 
< 



I 






of stones and substituting grooved chilled iron and porcelain rolls, making it 
a gradual reduction roller mill. 



58 MILL PLANS. 

The Burned Yaeger Mill, St, Louis, Mo. (AUis).— This large 
and beautiful mill was designed and built in 1876, and finished complete from 
the foundation up in ninety days from signing of contract. The building 
is 160 feet square on the ground. In Figs. 17, 18 and 19: "A" is the mill 
proper, 80 by 86 feet, consisting of basement, four high stories and attic. 
" B " is the engine house, 16 by 53 feet ; " C " is the boiler house, 48 by 53 feet; 
both of these are covered by one roof. The stack is 10 feet square at base 
and built up octagonal. " E " is the wheat drying house, 27 by 64 feet. " F " 
is the coal room, 10 by 70 feet. The cleaning house consists of the basement, 
in which is placed a small steam engine to pump water, and a repair shop, 
and has three stories above basement. The large room, "G," is used as a 
store house, 60 by 52 feet. "H " is the grain house, 60 by 28 feet. The whole 
basement underneath "G" and "H" is intended for store room, and the 
height is such that the barrels can be rolled directly into the cars. Above 
"G" is the bran storeroom, 52 feet wide. The wheat bins are 44 feet high. 
The railroad track runs alongside of the mill, from which to receive wheat 
and ship the product of the mill. The wheat is rapidly taken from the cars 
and elevated into the bins, and from the bins is taken to the cleaning 
machinery by conveyor and elevator. It is first put through three large 
separators, then through four dusters and two brush machines, and thence 
into two grading reels, from which it is put through eight large chilled iron 
crushing rolls, for the purpose of opening the wheat without making flour, 
from which it goes into two more dusting reels, for the purpose of getting rid 
of the dust and loose germs. It is now elevated and conveyed into the mill 
proper. This contains twenty runs of 4^-foot stones and fourteen of Weg- 
mann's patent porcelain roller mills. There are five 4-reeI chests and one 
2-reel chest (reels 32 inches by 25 f^et) on the fourth floor. On the third 
floor are five 4-reel chests and one 2-reel chest, and on the second floor are 
two 4-reel chests ; these latter, however, with reels, are only 18 feet long. 
Under each reel are double conveyors. In the attic there are four middlings 
grading reels and six 15-feet reels for roller products. The system of bolting 
and rebolting is very complete, and the bran is scalped off on the first reels. 
The system of purifying middlings is elaborate and perfect. The clean 
middlings from the upper machines are spouted to the rolls or stone, and the 
returns from these machines pass into other machines on the lower floor, and 
from these are taken to the rolls, etc. 

The machinery is driven by an automatic cut-off engine, and the boilers 
are made of steel. The stones are firm on iron hurst frames and are placed 
on either side of the main line shaft, from which they are driven by a 
quarter-turn belt. The spindles are 5-2- inches in diameter and 10 feet 
long. 




Fig. i8.— Side Section of Burned Yaeger Mill. 



[61] 



n- 




Fig. 19. — End Section of Burned Yaeger Mill. 



[62] 




r'li''ir!r'ii' irviriii;^f:ji^^''ir f 11 'iriiiviii II lirjh^^ ii ii 'i ii 



I I . 



j^ 




h///////J////;^ 



m/M///. v///////y , ' ^/////m/ - 



^■M/AmyA 



Fig. 20.— Deseronto Mill.— End Elev.\tion. (J.T. Noye & Sons.) 



[63] 



^^ 




<« 



o 

2; 



U; Q 



Q 

I 



O 

to 



[641 



f^tiMU-lft^?^ 





[651 



TWO-RUN BUHR MILL— SEVEN-RUN BUHR MILL. 



67 



Two-Run Buhr Mill. — Fig. 24 shows a small corn mill with one run 
of stones for wheat and another for com, John T. Noye & Sons designers. 
It is shown in side view in Fig. 25. 

Seven-Run Mill Riclimond City Mill Works .—The illustra- 
tions given in Figs. 26, 27 and 28, show a new process stone mill especially 
designed to make the entire product a straight grade of a high quality. 
There are five runs of buhrs for wheat and two for middlings, four puri- 
fiers, one bran duster, two flour packers, one bran packer, one pair of bran 
rolls, one pair of middlings rolls, thirteen elevators, sixteen reels arranged in 
two 8-reel chests, and one separate reel for grading. The wheat goes 
from the stock bins to the five wheat stones. The product of the five runs 





Fig. 26. — Seven-Run Mill (Richmond City Mill AVorks). — Fio. 27. 

is equally divided between the two upper reels in the upper chest, there 
being one elevator for each. These upper reels are clothed to take a part of 
the flour off at the head and all middlings off at the tail. The middlings 
which come from the tail of the two upper reels are dusted in the lower 
reels, and then pass through the grader to the several purifiers. After puri-. 
fication the middlings go to the two runs of middlings stones, and are then 
bolted separately on five reels of the other S-reel chest, arranged precisely 
like those in the first chest. Two reels in the same chest are used for the 
products from the rolls, and all flour is finished on the remaining reel and 
thoroughly mixed before going to the packers, or, if desired, that portion of 
the flour made from the middlings is packed separately as a patent brand. 




Fig. 28.— Seven-Run Mill (Richmond City Mill Works). 



168] 



OLIVER EVANS' MODEL MILL. 



69 




S 



< 

> 



o 
I 






Oliver Evans' Model Mill. — Fig. 29 is a copy of the panorama of 
a complete automatic mill designed and drawn by Oliver Evans about 1790. 



70 



MILL PLANS. 



The Mill Office. — There is no manufacturing business, that has reached 
the same perfection of working, which can compare with the miller's in 
mean, out of the way, dirty and uncomfortable offices. Stuck away under 
some back stairway, out of the reach of daylight, they become the receptacle 
for old cast-off overalls, samples and bethumbed papers. Everything is 
covered with a mixture of dirt and flour, as if those two went hand in hand 
in the output of the mill. This is a wrong principle. Aside from the con- 
sideration of cleanliness it does not pay to keep a dirty office. The office 
should be well lighted and ventilated, and should, if possible, be situated on 
that side of the mill receiving the least dust. Its size, of course, must be 
decided by each miller. It should contain a closet for garments and be 
divided into two compartments : one for the miller's use and one for visitors, 
so that the dusty garments of the miller may not come in contact with the 
clothes of his visitors. Fig. 30 represents a model mill office planned by 




nnnn'nnnnnnnnnnnnn nn nn^^nn^^nf^p 



u u u u u 



u u UUUi-iUlj u U U U — U UULiU UUULJLI — u U U 



Fig. 30. — Mill Office. 

A— High Desk. B— Chair Desk. C— Heaters. D— Washstand. E— Wardrobe. F— Sample Cases. 
G— Testing Table. H— Beam of Railway Scale. I— Railway Scale. J— Doors. K— Safe. 

Nordyke & Marmon. This plan is perhaps a little more elaborate than 
some mills can afford; but the principle on which it is drawn is, " Everything 
in its place and a place for everything," and if this principle, combined with 
cleanliness, shall be carried out in all the mills, the offices will be much more 
attractive and more convenient. 



-^ 



..o-JK-o- 



->- 



CHAPTER III. 

MILLING DIAGRAMS. 



Preliminary Mill Plans". — The diagram given, Fig. 31, was drawn 
by A. Forrest, now with the Novelty Iron Works, of Dubuque, Iowa, and is 
called by him a "Panorama of the Mill," because it brings all of the proc- 
esses of the mill before the eye at one view. The diagram was not designed 
to show the arrangement of a first class or a complete mill of any class, but 
was intended merely to show a method of sketching out milling processes by 
men who are millers and not machinists. The processes are sketched out as 
any miller might do it, without any reference to the location of the various 
devices in the building. Every practical miller and millwright will readily 
understand the construction of the several parts required to carry out the 
processes as sketched. AVhile this plan does not show a complete modern 
mill, yet, if properly arranged as to machinery, it would make a very good 
custom or exchange mill, of small capacity. 

In arranging the machinery of this mill, the millwright would, probably, 
place the "receiving hopper" somewhere on the first floor, not, as in the 
sketch, clear in the top of the mill. The " separator " could be placed on 
the first floor and the "smutter" in the basement. The stones, located so 
far apart in the drawing, would all be placed side by side on one hurst frame. 
The reels and conveyors shown would be placed in chests, standing on the 
first fioor side by side, and extending to the required height. The "mixing 
conveyor " would be placed crosswise under the flour spouts of the bolting 
chests, or some patent mixer would be substituted for it. The "packer bin" 
would be located on second floor. The purifiers would find a place on 
second floor, or one on this floor and one in the attic. The dusting and 
scalping reels might be in separate chests and both located in the attic, im- 
mediately over the chop and middlings flour bolts. The "stock bins "and 
"middlings room" would be side by side, over the buhrs. 

By taking a pencil and following closely the continuous lines of arrows, 
the reader will not only be able to follow each and every product through the 
mill, but will see the utility of this method of making preliminary plans of 
mills. We trace the wheat from the receiving hopper through the separator 
and smutter to the stock bins, which ends the "cleaning process." From the 
stock bins we trace the grain to the two runs of stones, which it leaves in the 
form of what is called by many millers "chop." The chop, being thoroughly 
mixed, is next taken to the head of the scalping reel. The product of the 



r 




1 


yf 


^1 ' 




a. 
I 






[72\ 



PRELIMINARY MILL PLANS. 



73 



fine cloth on this reel is carried, by means of a conveyor, into the head of the 
chop reel No. i, which has two conveyors under it, the first of which conveys 
each way to the flour spout near the head end of the reel. Cut-offs from this 




o 

2 






- ...y ^J»/;j .y»y,4,„^„j^ 



„,g f„i'n -ii'n ^•X'J, 



spout to near the tail of the reel allow so much of the product of this reel as 
is pure to go through the spout to the mixing conveyor. By the second con- 
veyor the cut-off, or such portion as is not sufficiently bolted, is carried, with 



74 MILLING DIAGRAMS. 

what passes over the tail of reel No. i, to the head of chop reel No. 2. Here, 
by the use of a similar arrangement of conveyors and cut-offs, flour is taken off 
to any desired extent, and run, with the flour of the No. i reel, to the mixer. 
The cut-off from this reel, by means of a properly arranged valve, is carried 
either into the upper or lower reel as the miller shall choose. All that is 
necessary to change the direction of this cut-off portion is to pull a string. 
What passes through the No. 2 cloth, on the tail end of the scalping reel, 
falls into the conveyor and is run into the head of the "middlings dusting 
reel." All middlings that may have passed through the chop reels will be 
taken out through the coarse cloth at the tail of the lower reel, and, as shown 
by following the arrows, join the middlings from the scalping reel and go 
into the dusting reel. What passes over the tail of the scalping reel joins 
similar material from the tail of the second chop reel, and goes to the room 
for offal. What is left is now safely cornered in the dusting reel. The prod- 
uct of this reel (what passes through the cloth) goes through the conveyor 
into the head of middlings reel No. i. The dusted middlings, passing over 
the end of the cloth of the dusting reel, goes to purifier No. i. By following 
the arrows, we trace the middlings through the machine to the middlings 
room. The tailings from purifier No. 2 go to the room for offal, although 
any other disposition may be made of them, if desired. From the middlings 
room the purified middlings pass to the "middlings stones." From the 
middlings stones we follow the reground product, by the arrows, into the 
head of middlings reel No. i. In this chest there is the same system of con- 
veyors and cut-offs as in the first flour chest, and the process is the same, 
differing only in the qualities of the silks. To the processes here traced out, 
a cockle machine and brush may be added to the cleaning process; a grad- 
ing reel to the middlings process, and a bran duster and even corrugated 
rolls for cleaning bran and tailings may be added. All of the cloths may be 
graded to suit the miller who operates the mill. 

In Fig. 32 is shown a plan for a mill, as laid out by John T. Noye & 
Sons, Buffalo, N. Y. 



-^ o-Jjc-u'' ^ 



CHAPTER IV. 

POWER. 



Waste of Power— Relative Cost of Steam and Water Power— Steam vs. Water— Power per Barrel 

of Flour. 

Waste of Po"wer. — There are some places where water is cheaper 
than steam power, and some just the other way. There are places where 
water ought to be cheap, but it is not. An instance of this is to be found at 
Moline, III, where there is one of the best water powers in the country ; but 
the water power company charges so much for water rents that many of the 
manufactories are changing to steam power. The cost of fuel may be 
greatly increased by an ignorant or careless engineer or fireman ; by bad 
boiler setting ; by a wrong type of engines, or a good type which is of 
the wrong size or badly set, or allowed to get out of repair. Slipping belts, 
or over-taut belts, will waste many pounds of coal or cubic feet of water. 
Sometimes ten dollars' worth of oil will save twenty dollars' worth of coal 
Too low or too high a chimney may waste coal. An unprotected boiler will 
take more coal to make the given weight of steam than one that is properly 
protected, and the steam will not be so dry. Gearing that is made by some 
country establishment by rule of thumb, or mortise gears in which the cogs 
are made by hand, will use up a good deal of power beside giving plenty of 
backlash. 

Relative Cost of Water and Steam Power. — The cost of the 
water equii^ment at Lowell was for canals and dams $ioo, and for wheels 
another $ioo per horse-power ; but this was too great. At one place 
reported the expense was $175 per horse-power. The cost at Penchet 
$113.50 per horse-power; with wooden dams and lower grade wheels, 
the cost is about $50 per horse-power, and, although this would be less 
permanent than the more solid installation, it would outlast any steam 
machinery. Fall River cost of steam equipments, e.xclusive of foundations 
and engine house, runs from $100 to $115 per horse-power. A Boston 
authority gives $115 per horse-power for nominal 300 horse-powers and 
upward, inclusive of foundation and masonry. A Portland authority places 
it at $100 per horse-power. A Western manufacturer says that, with six to 
eight feet head, the average cost for wheels, flumes, etc., is not far from !{i!2oo 
per horse-power, while at another point, with eighteen feet head, it does not 
reach I50 per horse-power. (The actual cost of the steam equipment in the 
vater works in the various cities of the United States varies from $150 

6 



76 PO WER. 

to $300 per horse-power.) The amount of masonry and excavation neces- 
sary vary greatly. We may say that the turbine itself and its installation, 
exclusive of excavation and masonry of races, etc., is from $40 to I150 
per horse-power. It must be borne in mind that estimates which would be 
applicable to Wilmington, Delaware, for instance, would not apply to 
Holyoke, Minneapolis, Appleton, etc. As most water-power contracts are 
awarded, the laws permit running at night, without extra charge, — no 
mean item of advantage. 

Steam vs. Water. — A steam mill has this advantage over a water 
mill, that it is almost entirely independent of the situation. It can be placed 
to suit the convenience of receiving grain, shipping flour, etc. But the 
water mill, as ordinarily constructed, must be built near the power, which, in 
many cases, is of itself a disadvantage, by reason of being there exposed to 
danger from high water and of having no dry basement for cleaning machinery 
or for storage. This difficulty might be largely overcome by the use of wire 
cable to convey the power of the fall from the wheel to the mill, which might 
then be put where convenient for everything. 

Power per Barrel of Flour. — At the Northwestern roller mill, 
Minneapolis, a 30-inch turbine, under thirty-eight feet head, and tabled at 
311 horse-powers, turned out for several days 800 barrels of flour per day of 
24 hours, which is at the rate of 0.388 horse-power per barrel. The Standard 
mill, in the same city, with a 44-inch turbine tabled at 320 horse-powers, 
under twenty-four feet head, has produced 900 barrels per day of 24 hours, 
being at the rate of 0.355 horse-power per barrel. C. C. Washburn, of 
Minneapolis, is driving his mills, B and C, with turbines, one of which 
is rated at 600 horse-powers, with which they turn out 1,400 to 1,500 barrels 
of flour per day of 24 hours. The Crown roller mill, Minneapolis, owned 
and operated by Christian Brothers & Co., made during the summer season 
of 1880, when running full, 1,000 barrels of flour per 24 hours, with a wheel 
of 400 horse-powers. 



CHAPTER V. 

WATER-WHEELS WITH HORIZONTAL AXES.* 



Kinds of Wheels— Undershot— Breast— Overshot— Vertical vs. Turbine Wheels— The Largest Water- 

Wheel— Screw Flood Wheels. 



Kinds of Water-Wheels. — There are four kinds of water-wheels in 
common use; overshot, undershot, breast and turbine, the first three having 
horizontal, and those of the fourth class vertical axes. 

The Undershot Wheel. — The earliest water-wheel is the "flutter" 
wheel ; next the undershot — at first with straight radial buckets, then with 
obtuse buckets, and then with curved, the last developing 60 per cent, of the 
water power. Undershot wheels are limited in power by the size of the floals 
and the velocity of the stream. Part of the force is lost at the ends and 
below the paddles. 

The Breast Wheel. — Breast wheels lose a great deal of watei unless 
kept close to the sheeting, and require a large portion of the total fall to be 
used as head, one foot of fall being equal to two feet of head. This is a 
disadvantage. In breast wheels the buckets should receive the percussion of 
the water at right angles, as this prevents the water from flying towards the 
centre of the wheel and at the same time holds it in the wheel to act by 
gravity after the stroke ; it admits air freely and discharges water freely 
without lifting it at the bottom. Where the water level varies, the breast 
wheel adapts itself better to the arrangement of gate than the overshot. 
Where the level falls, say 18 inches, it draws from the lower gate. The 
water, as it leaves the breast wheel, is forced away instead of submerging the 
wheel. 

The Overshot W^heel. — Overshots are not good where much jDower 
is required in a concentrated form. For high heads they require to be 
of too great diameter. They are generally made of wood, and are, therefore, 
liable to decay and give trouble from stoppages for repairs. There is 
an excessive amount of friction by reason of their great weight, and they 
are not well adapted for use where the water level varies. In this respect 
the breast wheel is better, as there can be two or more gates to accommodate 
different levels. Overshot wheels are more economical, proportionally, at 
part gate than turbines. They are slow moving and for most manufacturing 
purposes require too much gearing up to get speed. A 24-foot wheel should 

* Detailed instructions for building wooden water-wheels are given in tlie chapters on Millwrighting. 



78 WATER- WHEELS WITH HORIZONTAL AXES. 

make about four turns per minute. The fall is the distance between the 
surfaces of the water in the head race and the tail race. In overshot wheels, 
throughout that portion of the distance between the surface in the head race 
and the wheel itself, it acts by impulse only and not by weight. The full 
outside diameter of tlie wlieel does not have useful effect, liut there is some 




Fig. 33. — L.iiRGE Overshot Wheel. 



loss both above and below, say one-half of the depth of two buckets, equal 
to the depth of one bucket. 

Vertical Wheels vs. Turbines. — Vertical wheels (that is, wheels 
with horizontal axes; gencrnlly cost more to erect than turbines, except for 
low falls. Vertical wheels are. very much impeded by ice forming, while 



DIFFERENT KINDS OF WHEELS, ETC. 79 

turbines are not ; back water interferes with them seriously, and they are 
more difficult to erect than turbines. In all wheels there is loss by 
reason of the space between the wheel and gate; some by friction in gate 
and buckets and journal friction. 

The Largest "Water-Wheel. — One of the largest water-wheels in 
the country is the overshot which runs the Cascade mill at Akron, Ohio. It 
is 30 feet diameter by 10 feet face ; but one much larger is that shown in 
Fig. 7^7,, and which is over 50 feet in diameter. This is used to drive 
the factory of the New York Belting and Packing Company, on the Potatook 
River. Both of these great wheels are now supplemented by steam. 

Screw Flood Wheels. — The screw flood or spiral wheels are very 
little used. They are just like the propeller wheels of steamboats, except 
that they are stationary and the water moves ; while in the steam propeller 
the water is comparatively at rest and the wheel advances with the vessel. 
They are best made of several detached blades or vanes, instead of a con- 
tinuous screAV. The more rapid the current the more obliquely the vanes 
must be set in the direction of the stream. For very slow currents they 
must be set nearly across the stream. They must have a mold-board twist, 
giving the inner end more obliquity than the outer. In many situations the 
power can be taken from them by an endless chain of open malleable iron 
links, which answers best for this slow, heavy motion. In winter in cold 
climates, however, this chain will give trouble by carrying up water and 
covering everything with ice. Where there is ice, then, it will be preferable 
to take the power off of the down stream end from a narrow-armed cog 
wheel. There must be a boom or breakwater up stream to protect it. These 
wheels are much in use in Holland. There was one upon the Genesee 
River, between Rochester and the Alleghanies, before the Genesee Canal 
was built. This wheel was about 9 feet long with a 15-inch shaft, the screw 
being of pieces extending out about 2 or 3 feet from the shaft and widest at 
the outer end ; having a bar of iron twisted around the outer edge. The 
whole was inclosed in a box. 



-O-T^" ^- 



CHAPTER VI. 

T U R B I N i: S 



Tlieorv — Vertical Wheels vs. Turbines — Useful Eflfect — The Victor Wheel — OrderitiK Wheels— High 
Kails — Steps — Clogging — Variations of Power — Water-Wheel Governors. 

Theory of the Turbine. — The essential parts of a turl)ine wheel are 
an axis, having attached to it two crowns, between which are equidistant 
curved vanes or buckets, against which the driving current is directed simul- 
taneously at all points of the circumference by guide-blades not attached to 
the axis. The action of the water on any one bucket is repeated all around, 
and in analyzing the construction and operation of the wheel we may calcu- 
late as though there was only one bucket. 

There are five general principles applicable to turbines of all kinds: 
I. When a surface moves in a given direction under given pressures, the 
component pressures in all directions, except that of motion, are neutralized, 
either by reciprocal actions, or by fixed surfaces, which guide the moving 
surface. Therefore, in considering mechanical work done by given pressures 
acting upon moving surfaces, it is necessary to take into account those com- 
ponents only of the pressures which act in direction of the motion (friction 
being neglected). 2. In whatever direction a surface is moving with refer- 
ence to the earth, if the fluid moves along this surface in a direction opposite 
to the motion of the surface and with a relative velocity equal to the velocity 
of the surface with reference to the earth, the fluid will be at rest with refer- 
ence to the earth. 3. A fluid stream, striking a smooth surface at any angle 
whatever, is not reflected like a solid, but floAvs along the surface, a. If the 
surface is fixed, and the stream is confined in a channel of uniform dimensions 
before and after striking the surface, the velocity of the stream will remain 
unaltered (friction not being considered), b. If the surface is moving, the ve- 
locity under the same conditions after striking the surface will be the relative 
velocity of the surface and fluid before impact. If, for instance, a fluid jet 
impinges perpendicularly upon a plane surface moving with any velocity in 
the same direction, the relative velocity will be the difference of the two 
velocities, and this will be the velocity with which the stream will flow along 
the surface. This initial velocity gives rise to a pressure due to impulse, 
the direction of the pressure being always normal to the surface at the point 
of impact. -4. If the surface is curved the same phenomena occur, except 
that the relative velocity of the particle of steam is not entirely destroyed 
until it reaches a point at which it is moving at right angles to the direction 



THEORY OF THE TURBINE. 



81 



of the motion of the surface. 5. After the particle passes that point it flows 
along the curved surface without any further change of relative velocity, a 
change of curvature having no effect to change the velocity of flow relatively 
to surface. 

The effect of reaction results from the action of the water while in con- 
tact with the bucket, after it has attained the speed of the bucket. It is 
measured by the product of the mass of water times the relative velocity im- 
parted to the water in a direction opposite to the motion of the bucket times 
the velocity of the bucket. 

Nearly all modern turbines may be classed in three types or their 
combinations — viz., outward flow, inward flow or centre vent, parallel flow. 
In all cases the fixed guides give the water a tangential whirl as it enters 
the wheel. Whatever motion the fluid has with reference to the earth,' 
on leaving the vane, represents unutilized force. There is for every 
wheel a maximum velocity, beyond which there is little or no gain in 
going. Thu';, in one case, increasing the wheel velocity from .48 to .68 of 
the velocity due to the fall affected the efficiency only 2 per cent. Nearly 





Fig. 35. 

all of the theories of turbine construction which are going the rounds of text 
books are incorrect as far as applied to modern practice, and, in some 
respects, are quite the reverse of true. The effect of the water striking the 
curved vanes of a rotating wheel is due, according to the curve of the vanes, 
to either impulse or reaction, or to both. The effect due to impulse may be 
increased by the mass of water times, the velocity of the bucket times, the 
relative velocity of the fluid in the direction of motion of the bucket. The 
turbine differs from the vertical impulse wheel, in that the whole of the water 
in the turbine is acted upon by the water at the same time and continuously, 
and the water glides from the opposite edge to that at which it enters. 

If the water passes through the chutes aaa (Fig. 34), it will pass into the 
space between them and the wheel /;, and will be given a direction the same 
as that of the wheel, with a velocity of .7, and will issue out between the face 
c c in a. contrary direction, with equal velocity as regards the wheel ; but, as 
the wheel is moving with the same velocity without actual velocity, the actual 
course of the water will be the dotted line a c b f. If the water passes 
through the face (Fig. 35), its direction on leaving is by that of the dotted 
lines b b; but if it passes through aaa (Fig. 36), its direction will have that 
oi b b b, which will be a much greater change. If the face is formed like 
Fig. 37, with the top parts cycloidal and the bottom part tangential to the 
vextex of the cycloid, the greatest possible quantity of water will issue with 
the greatest possible change of velocity and direction. 



82 TURBINES. 

The water discharged from a turbine in operation giving out its maximum 
effect leaves the short discharge-tube moving in the same rotary direction as 
the wheel, and with a velocity nearly equal to that due to the effective head 
multiplied by the coefficient of discharge for the chute openings and dis- 
charge orifices of the wheel. In some wheels the discharge openings of the 
wheel are larger than the chute openings of the casct In others, the dis- 
charge orifices are smaller than the chute openings. The discharging water 
from the turbine tends to spread horizontally from the moment it escapes 
from the short draught-tube, moving in curved lines towards the horizontal 
lines. Below the draught-tube there is a body of water having a movement 
of rotation, from one side of which there is a volume of water throwing off 
tangently but slightly crosswise of the tail-race if closed. The quantity of 
water discharged through the flume opening of a wheel going under an 
effective head, when the chute openings are fully open and the wheel is 
removed, is about the same as that discharged when the wheel is in the case 
with chutes fully open and doing its best work under the same effective 
head. The faster a turbine revolves, the less it will realize of the head due 
to the hydrostatic pressure, and the slower it revolves the more it will realize. 

A question is sometimes put as to whether a turbine wheel can run faster 





Fig. 36. 

than the water which drives it. It is apparently a paradox if it is the case. 
but none the less impossible. Water tends to press on all sides alike. If all 
of the outlets of a wheel should be closed, it would not move, being held in 
equilibrio. If the wheel moves with the same velocity as the issuing water, 
no work will be done. If the wheel moves with less velocity than the 
effluent water, work will be done. To produce a maximum effect, the wheel 
should move just one-half as fast as the water that issues from the wheel. 
The velocity of water issuing from a head will be as the square root of 
the height, and will be something near .7 that due to the whole head. 
If a reaction wheel, moving with a velocity of .7 that due to the 
head, has the water let on it in the direction of its motion through a 
chute or chutes equal to that of all the issues of the wheel, the velocity 
of the water and of the wheel will each equal .7 and the pressure of the 
water on the wheel will be equal to .5 the whole head. The water will act 
upon the wheel just as if both were at rest, and will, therefore, issue from the 
wheel with a velocity due to one-half the head, that is, .7 as relates to the 
wheel ; but, as the wheel moves with the same velocity in the same direction, 
the water leaves the wheel without actual velocity. As the wheel moves with 
a velocity equal to that of the effluent water, and with a force equal to the 
weight of one-half the whole column of water, the duty is 50 per cent., or 
double what it would have been had it been let on without a motion in the 
direction of the wheel. Water issuing from an aperture in a thin plate will 



VERTICAL WHEELS vs. TURBINES, ETC. 



83 



have a discharge equal to .62 that assigned by theory. If we apply to the 
aperture a tube of equal size throughout, and with a length equal to 
twice its diameter, the discharge will be .80. But, if we fix a cone-shaped 
tube inside of the vessel, the discharge will be very nearly that due to theory. 
Vertical Wheels vs. Turbines. — A gentleman of ample experience 
remarks: " The first requisite in a good mill is good motive power, and 
among all hydraulic motors yet discovered none can compete with a good 
turbine, for the following leading reasons : The turbine is not affected by 
ice; it is not affected by back water, save the loss of power due to the loss of 
head; it is much cheaper in first cost; it is more cheaply and easily trans- 
ported and erected; it is suited for all heads and all locations; and above all, 




\'^^.^' C^icrbVol 



T,:.-. \T_>.tv 



Fig. 38. 



it is more economical in the use of water, for its high velocity dispenses with 
the cumbrous double gearing which is absolutely necessary with under or 
over shot wheels, with which, as experience has abundantly proved, about 
one-third of the power of the water is expended in simply obtaining velocity, 
or overcoming the inertia of matter." Turbine wheels require a less height of 
stone foundation than other wheels. The overshot wheel splashes about, 
and causes rot unless the wood work is quite high; but there are cases where 
it is not convenient to have the millstones above their splash level, as for 
instance where it is desirable or necessary to have the stone floor near the 
road level for teams. 

Overshot vs. Turbine. — Fig. 38 is intended to show why an over- 
shot wheel will not always yield the full power of the water. It shows an 
overshot wheel and the flume of a turbine to do the same work, the head and 
fall in both cases being 18 feet (a fair average). Of this it is customary to 



84 



TURBINES. 



allow 2 feet for head above the overshot, and 6 inches to prevent the wheel 
wading in tail water, limiting the diameter of the wheel to 15-^ feet. As 




Fig. 39. — Overshot. 

the wheel begins to empty at some distance above the level of the water 
in the tail race we may take off another foot of fall as lost, leaving 14-^ feet, 



OVERSHOT vs. TURBINE. 



85 



or only about 80 per cent, of the whole fall used. The turbine being at the 
bottom of the flume uses every inch of head and fall. 




Fig. 40. — TiRBiNE. 



Figs. 39 and 40 are intended to show the advantage of a turbine, for 
high falls, over an overshot wheel. The overshot shown is of 22 feet diam- 



86 



TURBINES. 



eter by 3 feet face, to work under 24 feet head and fall. The bevel wheel B 
is 12 feet diameter; spur wheel D is 9 feet. The upright, running only 20 
turns per minute, must be very heavy — in this case 8 inches in diameter. 
The shaft H must be at least 4 inches in diameter. It will be seen that all of 
the parts are very heavy and that friction is necessarily very great ; while the 
cost is excessive. The other cut shows an ii-^-inch turbine, which will give 
more power than the 22-foot overshot. Instead of the 2-foot shaft of the 
overshot, or an iron shaft of 10 inches, there is simply a i;|-inch wrought-iron 
shaft; while there is needed only a lo-inch iron pulley weighing 30 pounds, 
from which the belt runs directly to the buhrs. Instead of the 4 to 8 inch 
shaft H, there is a light i-^-inch shaft. Instead of gearing up for the speed 
of the smutter, by a spur wheel M, and the pinion N, and pulley, none 
of this gearing is required, as the wheel makes nearly 600 turns. 

Useful Effect. — A good turbine will develop over 80 per cent, of the 
useful effect of the water; but the fancy tests published are generally made 
with special wheels with Russia iron or graphited guiding surfaces, and under 
exceptional conditions, during a short run only. The following tests of the 
Victor wheel were made in the Holyoke flume by James Emerson, and are 
stated to be made on regular-made wheels taken from stock : 



Size of Wheel and Date of Test. 



25-inch Victor turbine 

Tested October 28, 1878. 

30-inch Victor turbine 

Tested October 29, 1878. 

15-inch Victor turbine 

Tested March 26, 1878. . 

15-inch Victor turbine 

Tested August 23, 1879. 

20-inch Victor turbine 

Tested May 21, 1880 

15-inch Victor turbine 

Tested April g, 1880. . . . 



Head 

in 
Feet. 


Revolu- 
tions 
per 

Minute. 


17-79 


205.5 


17 


96 


209 




II 


65 


144 


5 


11 


66 


147 


5 


18 


34 


323 




18 


10 


321 


5 


18 


06 


368 




18 


08 


355 




18 


22 


286 




18 


23 


275 




18 


21 


269 


5 


17 


97 


348 


5 


17 


98 


347 


5 


17 


98 


337 


5 


17 


98 


323 




17 


99 


334 




18 


02 


331 


5 


18 


09 


339 


5 


18 


20 


339 




18 


38 


334 







Cubic 


Per- 


Horse- 


Feet 


centage 


Powers. 


of 


Useful 




Water. 


Effect. 


67.72 


2362.72 


.8530 


68.62 


2356.54 


.8584 


52.54 


2751.87 


.8676 


51.96 


2755-09 


.8564 


29.36 


973-75 


•8705 j 


29.22 


970-39 


.8808 


30.17 


990.19 


.8932 


30.12 


996.83 


.8S49 


48.75 


1660.17 


•8532 


48.75 


1660.17 


.8528 


49.00 


1671-57 


.8522 


Full Gate. 






30.62 


974-47 


-9258 


30.53 


972.80 


,9242 


30.66 


977-81 


■9234 


30.36 


981.15 


.9111 


Part'l Gate.* 






29-35 


971-13 


.8896 


26.11 


901.88 


-8506 


23-14 


808.53 


.8376 


17-97 


695.06 


-7538 


;o.62 


482.59 


•6345 



♦Part gate does not mean any fixed position of the gate wheel, nor does it refer to the amount of 
gate opening, but to the amount of water used by the wheel as determined by measurement on a weir. 



USEFUL EFFECT— THE VICTOR TURBINE. 



87 



The makers state that all of these wheels were plain cast-iron wheels, and 
were tested for purchasers, except the last named wheel, which was furnished 
to the Holyoke Water Power Company for the purpose of making some ex- 
periments on gears, belts, draft tubes, &c. It will be observed that steady 
improvement was made subsequent to the date of the first test. 

A 17-J-inch wheel, tested by C. Herschel, engineer for the Holyoke Water 
Power Company, on August 5, 1880, yielded .896 per cent, useful effect. 

Machines furnished by many builders specially for competitive test do not 
give the same results as those taken from stock; and an excellent way for the 
buyer to secure himself against loss or imposition, in cases of machines which 
have guarantees published, is to stipulate that the purchased machines shall 
under the same conditions give the same duty or no pay. It is useless to buy 
a turbine which will give a duty of 85 per cent, or over for one day only.. 
Such tests are of little value to any one. Some wheels, giving excellent results 
under test conditions, will go to pieces with the rough usage of regular work. 




Fig. 41. — Outer Chute Case (Victor Wheel). 

The only satety in such a matter is to buy only wheels of high reputation for 
durability and long continued efficiency. There are some wheels which are 
extremely bad about burning out their steps. A good plan for testing tur- 
bines would be to fix the standard of speed, at which the wheel shall run while 
at labor, at the velocity at which it produced the best results when working 
under three-quarters gate (instead of at full gate as is customary), especially if 
the wheel is to be run mainly at partial gate, for the wheel when running at 
partial gate requires a little slower motion to develop its best results than when 
running at full gate. This is in any case true of wheels of large capacity. 

The Victor Turbine, — In setting forth the advantages of the \'ictor 
wheel and its claims upon public confidence, the makers state that all of the 
work in fitting it up is performed by machinery, every separate part being fit- 
ted to a standard gauge. By this means dupficates that Avill fit can be fur- 
nished at any time. Following is a description of this wheel : 

Fig. 41 is the outer chute case and cylinder, with the bridgetree and 
wood step which support the wheel, in position. The case is one casting, 
and after receiving the bridgetree, which is secured by set screws as shown,. 



88 



TURBINES. 



is placed upon a horizontal boring mill, and is bored out to receive the 
register gate (Fig. 42), which revolves within it. It has a projecting flange, 
which rests upon the floor of the penstock, and this flange is faced off true, 
at a right angle with the wheel shaft, so as to insure the wheels setting plumb, 
provided the floor of the penstock is level. 

Fig. 42 illustrates the inside register gate, which is cast in one piece, with 
fixed water ways corresponding with the chutes in the outer case — the two 
combined forming one duplex chute. This gate is bored out to receive the 




Fig. 42.— Register C^te. 

wheel and is turned off to fit the outer case, within which it revolves, and is 
moved, for the purpose of admitting and shutting off the water, by means of 
a segment and pinion. The movement of this register gate regulates the 
amount of water supplied to the wheel, and secures an equal and uniform 
delivery on all parts of the wheel, without changing the direction of the 
current or the relative angle of the stream and the face of the bucket, or 
greatly checking the velocity of the water admitted to the wheel. There is 
a four-armed spider, attached to the gate as shown in Fig. 42, the hub of 
which is bored out to fit accurately upon the lower end of the pedestal, 




Fig. 43. — Top of Wheel Case. 

which projects beneath the top of wheel-case and forms a journal-bearing, as 
shown in Fig. 43. The makers state that this improvement in its practical 
workings is of great value. It enables them to fit the gate so very close that 
it cannot leak, and yet have it work easily ; it strengthens the gate, holds it 
rigidly to shape, reduces the friction in moving it to its minimum, and as nearly 
as possible obviates the objection hitherto urged against a register gate. The 
merits of this gate, composed of one single casting, instead of a complication 
of butterflies, rings, rods, and bolts, will be apparent. Fig. 43 represents the 



THE VICTOR TURBINE. . 89 

top of the wheel case with the pedestal attached, through which the wheel 
shaft passes. The projection of this pedest-al underneath the top, and pass- 
ing through the hub of the gate-spider, forms a feature of lately patented im- 
provements, as previously mentioned, and is so clearly shown by the artist as 
to be readily understood. 

As will be seen, this top is composed of a single strong casting. It extends 
over the register gate, and is fastened by set screws to the outer chute case. 
This arrangement protects the gate from vertical pressure of the column of 
water and renders its movement very easy. This simple arrangement also 
greatly facilitates the erection of wheels, or obtaining access to them in case 
of accident, as by simply removing the set screws the top becomes detached. 

The pinion and segment by which the gate is operated are housed to pro- 
tect them from breakage by foreign substances getting in between the teeth. 
The cap of this housing, as shown in Fig. 45, may be detached by removing 




Fig. 44. — Victor Wheel Removed from Its Case. 

two set screws. This protection of the pinion and segment is of great value. 
The pedestal, which surmounts the wheel case, after being faced off true, 
is fastened to the top or crown plate by set screws. The seat below the 
follower blocks insures a rigid upper bearing for the wheel shaft, independent 
of the follower blocks and, in connection with the arrangement of the 
bridgetree that holds the step for the wheel shaft, secures steadiness of 
motion, low friction, and strength and durability. 

Fig. 44 shows the Victor wheel on its shaft removed from the chute case. 
The wheel presents some decidedly novel features. It receives the water up- 
on the outside and discharges it downward and outward, the lines of discharge 
occupying the entire diameter of the lower portion of the wheel, excepting the 
space filled by the lower end of the shaft. 

Fig. 45 shows the wheel as it appears when shipped to customers, ready to 
set in the flume. As will be observed, the chute case and gate are substan- 
tially the same in construction and operation as those used for several years 
past in the " Eclipse " wheel. 




Fig. 45. — Victor Wheel and Case Complete. 




Fig. 46.— Ikon Penstock. 

fiWI 



THE VICTOR- TURBINE. 



01 



The prices of the Victor turbines are given as follows : * 

6 inch wheel, made of brass, .... Price ?52oo 



lO 
12 

15 

20 



30 

35 
40 

44 



iron and brass, 
iron, 



215 
225 
240 
250 
290 
325 
435 

550 
700 

875 

HOC 



48 ... " 1300 

The above price list is for wheels complete, ready to set in the pen- 
stock, delivered free on board cars at Dayton, and includes hand-wheel, 
gears, and pawl and ratchet for operating the gate, with short pieces of shaft- 
ing fitted in each. In ordering wheels state whether they are to run with the 
sun, or against the sun. 

Appended is a table of dimensions of the "Victor" turbine. The lettered 
columns in table correspond with the dotted lines in Fig. 47. 



4) 


(a 


A 


B 


C 


D 


E 


F 


K 




u 

■So 

c ^ 

< 


J. ^-A 

Q 


IP 

So 
Q 


a 
S 


Length of Shaft 
from Flange Rest- 
ing on Floor of 
Flume to Centre 
of Coupling. 


5° 

'~~5. 

°|i 

15" = 

.loQ 
Q 


lei 

111 


S CJ ^ 

.■a >- -■ 

II sl 

Q 


Inches. 


Inches. 


Inches. 


Feet. 


Inches. 


Inches. 


Inches. 


From 2 to 6 feet deep, according to 
size of wheel and quantit)' of water used. 


Lbs. 


6 

8 
10 
12 
15 

i7>^ 
20 

25 
30 
35 
40 

44 
48 


93/ 

I3>^ 

16 

20^ 

23 
26 

30 

35 

\oYz 

46 

52 

56 

60 


11% 
16 
18 
18 

30 
32 
40 
46 
51 

57 
61 
66 


2 
2K 

3 

VA 
4 

5 

6 

8 

9 
10 
II 

12 


15 

18 

21 

25 

29K 

32 

33 
40 

47^ 
55;^ 
5914: 
63 

65>^ 


1 5 
T5 

lA 
If 
If 
iH 

2i 
2| 

3A 
3i 
4l 
4l 
51 
5| 


2/8 
2K 

31^ 
41^ 
5^ 
6 

63/ 

7K 
8K 

II 

12 

123/ 
I3>^ 


715 
925 

1175 

21 OU 

3100 

4500 i 

6450 

7850 

9425 



Column A also indicates the proper size of hole to be cut in floor of flume to 
receive the wheel. 



* August I, 1881. 



92 



TURBINES. 



Correspondence indicates a frequent misapprehension of the meaning of 
the term " square inches of water vented." Some think that in a wheel said 
to use " too square inches of water," it is meant that the entire area of the 
chute apertures measures loo square inches ; others think the meaning to be 
that the entire area of the discharge apertures is loo square inches. Neither 




of these views is correct ; but the meaning is that the theoretical discharge 
under any head, due to an aperture measuring loo square inches in cross 
section, would equal the actual discharge of the wheel under the same head. 
A " square inch of water " means a stream exactly one inch square and equal 
in length to the theoretical velocity in feet per second due to the head from 



THE VICTOR TURBINE. 



93 



under which it issues. For a head of four feet this length would be 16.04 
feet per second ; for a head of ten feet 25.36 feet per second. This velocity 
in feet per second, and the equivalent of a " square inch of water" expressed 
in cubic feet per minute, under heads of from i to 40 feet, appear in the 
table: 



25 in. wheel uses 180 square ins. water. 
248 
383 

459 
521 
614 



6 in. wheel 


uses 12 square 


ins. water. 


25 


8 




19 " 


" " 


30 


10 " 




33 " 


* ' * ' 


35 


12 




50 " 


(( 1 ( 


40 


15 




73 " 


». • ( 


44 


17K " 




96 ■' 


" " 


48 


20 " 




119 " 


" .t 





VELOCITY AND DISCHARGE OF WATER THROUGH SUB- 
MERGED ORIFICES. 

Table showing the theoretical spouting velocity of water in feet per 
second and number of cubic feet discharged per minute, through an orifice 
of one inch area, under different heads, from one to forty feet. 

(Calculated from Francis' Formulas.) 





■o 


1 u 




■a 


J. « 




■a 


1 u 

c w 




•a 


1 u 

G 




c 





i^ 




c 




S^ 




3 





•^H 




3 





S^ 




<^ 


>-o 




V 


i-O 




u 


■^O 




<u 


i-O 




u 




C/2 


u 




C/3 


V 




t/i 


(U 





. 


a-s 


a; 




c^ . 


0) 




o-'S . 


V 




t^ . 


to 


J) 


aj OJ 


!x. 




|S3| 


^ 


1) 


Ss| 


fc 


OJ 


ss| 


_c 


i>,^ 
Ca 


£<5 


c 


>>s 


^^^ 


3 


^S 


f^^" : 


^3 


>^s 


=^<" i 


■6 

s 




■§30 


<A 


•2.S 


■§30 




■olx. 

I.S 


'U 1 

33O 


■a 

V 


.He 


•5=0 


K 


> 





II 


> 





X 
21 


> 


. 


X 


> 





1 
I 


8.02 


3-34 


26.50 


11.08 


36.75 


15-31 


31 


44-65 


18.60 


2 


11-34 


4-73 


12 


27.78 


11.57 


22 


37.62 


15-66 


32 


45-37 


18.90 


3 


13-89 


5-78 


13 


28.91 


12.05 


23 


38.46 


16.02 


33 


46.07 


19.20 


4 


16.04 


6.68 


14 


30.00 


12.49 


24 


39- 29 


16.36 


34 


46.76 


19.48 


5 


17.93 


7-47 


15 


31.06 


12.94 


25 


40.10 


16.71 


35 


47-45 


19.76 


6 


19.64 


8.18 


16 


32.08 


13-36 


26 


40.89 


17.04 


36 


48.12 


20.05 


7 


21.22 


8.84 


17 


33-o6 


13-77 


27 


41.67 


17-36 


37 


48.78 


20.33 


8 


22.68 


9-45 


18 


34.02 


14.18 


28 


42.43 


17.68 


38 


49.44 


20.60 


9 


24.06 


10.02 


19 


34-96 


14-57 


29 


43-19 


17.98 


39 


50.08 


20.87 


ID 


25-36 


10.57 


20 


35.87 


14.94 


30 


43-93 


18.30 


40 


50.72 


21.13 



The Victor is a flume wheel, constructed to rest, by the flange of its case 
or stationary part, upon the floor of the flume, over an aperture in the floor 
through which th€ water is discharged. No particular form of flume is re- 
quired, but it is necessary that the foundations be made perfectly secure to 
avoid settling or getting out of level, and its strength in all directions should 
be sufficient to sustain the pressure of water under any circumstances. The 
floor timbers should be placed in the direction of the current, with their up- 
per surface at the height of standing tail water. The pit under the wheel 
should not be less than two feet below the floor timbers, and from three to 
six feet for large wheels. This pit should be extended out into the tail-race 



94 TURBINES. 

its full width and depth for several feet beyond the outside of the penstock, 
and then gradually sloped upward to the general level of the bottom of the 
tail-race. Too much importance cannot be attached to this matter of pro- 
viding ample space for the wheel to discharge into ; for, if there is not suffi- 
cient space in under the wheel to admit of the water's passing away from the 
wheel quietly and easily, it will react upon the wheel and seriously interfere 
with its performance. To ascertain the requisite size of flumes and tail-races, 
use the following simple rule. The makers' tables of power, etc., will indicate 
the proper size of wheel to produce the required power and also the number 
of cubic feet of water the wheel will discharge per minute. Divide the num- 
ber of cubic feet stated in the tables by 85, and the quotient will be the area 
in square feet required in the cross section of the head or tail-race for every 
wheel used. That is to say, for every 85 cubic feet of water used by the 
wheel or wheels per minute there should be one square foot in cross section 
of all the water passages leading to and from the wheel, including of course 
the opening under the penstock, through which the water passes after leaving 
the wheel. The pit into which the wheel discharges must never be less than 
two feet deep for small wheels, and increased to three, four, five and six feet 
in depth for larger wheels, according to their size, and of suiificient width to 
produce the area in cross section mentioned in the above rule. Larger water 
courses than indicated by the above rule are not objectionable, but desirable; 
for, the nearer a state of rest the water can be brought to before entering and 
after leaving the wheel, the better will be the results obtained. In improving 
a water power, properly constructed water courses will amply repay the labor 
and money expended upon them, and are essential to the proper working of 
any wheel. 

Sometimes in adapting wheels to very high heads, to avoid an excessive 
length of shaft on the wheel, and to otherwise conform to tlie peculiar loca- 
tion, it becomes necessary to set the wheel at some distance above tail water, 
and conduct the water away from the wheel through a draft-tube. The same 
depth of pit and area of discharge are required where a draft-tube is used as 
would be were the wheel set at 'the bottom of the fall. Theoretically, draft- 
tubes may be used of any kngth up to thirty-three feet, but practically it is 
unadvisable to use draft-tubes exceeding twenty feet in length, because of the 
difficulty in making and keeping them perfectly air tight ; and if the draft- 
tube leaks air at all, the vacuum is imperfect, and loss of power, due to the 
loss of head, is the result. A draft-tube, if used, must be of sufficient internal 
diameter to receive the cylinder of the wheel case. If constructed of wood, 
it should extend up through the opening made in the floor of the penstock, 
flush with the face of the cants upon which the wheel case rests, and be firm- 
ly secured to the penstock by spikes or screws, and be securely banded at 
frequent intervals with iron hoops. If constructed of iron, which is far pref- 
erable to wood, the ring or flange to which the tube is riveted should be faced 
off true, and let into the cants, so as to form a perfect joint with the flange of 
wheel case. As a rule on all falls of moderate height, the wheel should be set 
at the bottom of the fall. But in all cases where a draft-tube is used, it is best 
to have one made of boiler iron, so as to secure durability and tightness. 



ORDERING WHEELS— HIGH FALLS. 95 

Ordering' Wheels. — In asking about a wheel to do a certain amount 
of work some merely say, " I have so many feet head," saying not a word 
about the quantity of water. Some say " I have so many cubic feet of water 
per minute," and do not give the head. Others ask, "With what size wheels 
can I grind so many bushels per hour ? " 

Now in ordering a wheel, or in asking for information, the following data 
should be given : Head of water when at rest, or the vertical distance from 
the surface of the head water to that of the tail Avater. If there is only a 
small supply, state what is the most that can be relied upon, as measured 
and calculated from the de]:)th and width of flow over a properly constructed 
weir board. If there has been an overshot, this information may be got at 
by knowing how wide the wheel was, and how much the gate was raised to 
let the water on to it, and how deep the water was above the gate opening in 
the fore-bay. If there is plenty of water, state width and depth of the stream 
and speed in feet per minute of a board floating on its surface in the middle. 
If there is a turbine or a reaction wheel, already running, how many square 
inches of opening, and how many hours per day the stream will supply it. 
What kind of machinery is to be run (as full details as possible). If it is for 
corn or wheat ; whether an old or new building and old or new process, buhr 
or roller. Size and number of buhrs and of rolls ; how many bushels of grain 
each is grinding per hour ; how many hours per day, and whether you wish 
to grind more. State whether or not all are to be running at once. If all 
are not to be running at once, how many are to be ; speed of the main hue 
and shafting and if upright or horizontal. If the power is to be taken off 
above the level of the head of the water, the distance from the head of the 
water level to the level of the bed of the stones should be given. If the 
power is to be taken off below the head water level, by using a Decker flume, 
give the distance from the centre of the horizontal power shaft below the 
head water (or the distance above the tail water) when at rest. When there 
are many connecting gears, state whether spur or bevel, and the number of 
cogs, width or face of drivers on the pinions. State whether the turbine is to 
run in the same direction as the hands of a watch, or in the opposite direction. 

High. Falls. — The turbine of St. Blasien has 350 feet fall, and gives 73 
horse-powers. And the double turbine at Saltillo has 160 feet fall, and jjro- 
duces 125 horse-powers from 1850 revolutions of wheels 11 inches in diameter. 

About the only trouble with turbines is burning out steps. The step is 
generally made of lignumvitae, but any hard wood will do to replace it if 
worn. Apple is good. The form of the step is generally very bad. In all 
cases there should be some way of insuring that the step shall be kept sup- 
plied with water to prevent heating and burning oTit. Every now and then 
some one writes to the papers or consults an expert to know why his turbine 
step burns down ; or if he knows why, he wants to know what will sto]) it. 
The wood steps of turbines burn down because there is absolute contact be- 
tween the rubbing surfaces. One remedy proposed is to have creases cut in 
the step and the concave, through which creases water may circulate. Care 
should be taken that the heart of the wood comes in the centre of the stei>, 
to insure even wear. ' 



96 TURBINES. 

Clogging. — There are some turbines which will choke up with bark, 
leaves, or even coarse sawdust, and must be cleaned out at certain times of 
the day. In some places eels give a great deal of trouble in their periodical 
migrations down stream, in the fall. Eels give trouble because they can glide 
through most racks but cannot go through the wheels. Muskrats, which are 
such nuisances, for many other reasons, to those using water power, cannot be 
kept out of the wheel by a rack, as they climb over it or even force their way 
through by bending the bars. 

Variations of Power. — There are two ways of overcoming the varia- 
tions in resistance and in the head and height of water. The first is to have 
one or more turbines connected to the general shaft, each one or more of 
which can be detached at will. The second is the opening and closing of 
gates. 

Whether the mill is driven by steam or by water there will be a ten- 
dency toward variation of speed caused either by increase of force in the 
motive power, by decrease in the load upon the machinery driven, by throw- 
ing on or off one or more machines, by the breaking of a belt, gear, or shaft, 
or the loosening of a shaft ^oupling. If the motor is [)roperly regulated, such 
tendency to change of speed should be noticed at once by the governor ; and 
the more sensitive and powerful the governor is, the more evenly the machine 
will keep on running. With unsteady water power, millstones are apt to jump 
with light feed, although they will run steady with heavy feed. This trouble 
is aggravated if the mill is geared too high. 

Water-Wheel Governor. — To be of service, a water-wheel govern- 
or should be of sufficient strength to operate the gate of any of the ordinary 
turbines on the market; it should be durable, compact, and above all 
things should not "dance," but give a regulation at once without at first re- 
ducing the speed too low and then regoverning to too high a speed. 

A water-wheel governor manufactured by A. W. Woodward, Rockford, 
III, is shown in Fig. 48. In this governor the pulley is 10 inches in diameter, 
3-inch face, makes 135 revolutions per minute and should be driven with a 
2-2--inch belt. The shaft ^, which runs continually, has a slight lateral move- 
ment as the balls rise and fall, being connected with the same by means of the 
grooved collar b, rock-shaft e, and bent lever o. The lever o is made with a 
spring joint which opens when more pressure is applied than is necessary for 
opening the gate. The beveled pulleys a, a run loose on the shaft g and 
have pinions d attached to their hubs and are held in place by means of 
grooves at the end of the hub. By means of a screw x the position of the 
pulley a' can be changed, giving any required distance between a and a , 
making the governor more or less sensitive as required. Inside of the pulleys 
a and a is a pulley / beveled on the rim to the same angle with a and a', 
covered with leather, and turned to a perfect fit with a and a ; this ])ulley 
/ is fastened to the shaft g and runs continuously. A stop-nut jt moves 
back and forth on the shaft tn as the governor opens and shuts the gate; 
a lever 71 on the rock shaft is made to adjust by means of a set screw so that 
the nut s will strike it when the gate is full open, preventing the pulley / 
from coming in contact with the pulley a' , the spring joint in the lever allow- 



WATER-WHEEL GOVERNOR. 



97 



ing it to do so without interfering with the movement of the balls. At a- 
point shown by a dot on the lever, o, is a pin which projects so that the 
nut s strikes it when the governor has closed the gate sufficiently to allow 
the wheel to run nearly to speed with no machinery attached. This move- 
ment destroys the connection of / with a but allows the nut to travel along 
the shaft until the gate is closed, which must be done by hand. The object 
of this stop, when used at part gate, is to obviate a difficulty where a large 
amount of machinery is thrown off at once, causing the wheel to run at a high 
rate of speed and continuing to run above the speed of its own momentum 
after a sufficient amount of water has been shut off. It often happens in 
such cases, where the governor is allowed to shut off water until the speed is 




Fig. 48. — Friction ^Vatek-Wheel Governor. 

slackened, that the machinery is again thrown on at the instant when there is 
not enough on the wheel to run it to speed, let alone the additional power 
required to start the machinery. It also has a brake to hold the gate where 
it is inclined to close itself, so constructed that the greatest amount of 
friction is brought to bear when the gate is being closed, and less when it is 
being opened. 

The advantages claimed for the Woodward governor are : i. That the 
movement is continuous and not intermittent, and allows the gate to be 
moved to position in much less time with a slower movement than that given 
where pawls are used. 2. It is sensitive and requires only a slight change 
in the position of the balls for the governor to act on the gate. Of the total 
weight of the balls, two to five ounces thrown on the friction wheels are sufiS- 



98 TURBINES. 

cient to move any ordinary gate. 3. It is an easy working machine and 
therefore requires little repairs. The makers state that they have governors 
that have run for six years, with the exception of Sundays and holidays, 
without any repairs whatever. 4. The manner in which the friction wheels 
act in changing tlie position of the gate, gives the precise movement that is 
desired for what is called a differential governor without any extra device 
for that purpose. 5. It gives a quicker movement when opening than when 
closing the gate. (A recent improvement.) 6. It is not only provided with 
an open gate stop but has one that can be used at closed gate or part gate as 
may be desired. 7. It has sufficient power to handle any gate. 



^%<^ 




CHAPTER VII. 

SETTING WHEELS, ETC. 

Setting Wheels — Areas of Races and Flumes — Building Flumes — Position of Flumes— Decked Penstock 
— Details of Raised Penstock — Low Falls — Open Penstock — Wooden Flume for Turbines under 
High Falls— Sizes of Gripes — Draft Tube— Racks— Flood Gates. 

Setting "Wheels. — The wheel pit must be excavated of sufficient depth; 
and it should have a bottom of 2-inch plank on mud sills, unless there is rock 
bottom. This pit should be from 2 to 6 feet deep, extending out into the tail 
race its full width and depth for several feet beyond the outside flume and then 
gradually sloping up to the general level of the bottom of the tail race. The 
wheel must have ample discharge space. In case of clay or gravel formation, 
the flume should be stiffened by sills and posts, as it has a very heavy load and 
pressure to support. If it lags it will throw the wheel out of plumb. Silis 
must be of good, sound, durable timber, of ample size, and well framed to- 
gether, and when placed must be properly level and solid. The penstock 
should never be smaller in the square than three times the diameter of the 
wheel. The larger the better, however. For wheels above forty-eight inches 
twice the diameter is large enough for the penstock. The penstock must be 
supported by proper pillars of wooden blocks or good stone, holding the sills 
in a permanently level position. The mud sill or under foundation must be 
of a most secure and permanent nature, allowing no chance whatever for any 
under settling or any possibility of being undermined. Heavy trimmers of 
good, stout timber must be neatly framed in bands across the sills to receive 
the floor, which must be well and tightly laid with thick plank (from 2-^- to 4 
inches). The plank should be broad, say 18 to 24 inches. The floor timbers 
should be placed in the direction of the current, with their upper surface at 
the height of standing tail water, unless a draft tube is used. In large flumes 
each corner of the square opening left in the frame floor to receive the cylin- 
der wheel case, should be supported by a 3 or 4 inch square post of hard, 
stiff timber, braced solidly on the foundation ; while the bottom of the flume 
should be covered with 3-inch plank and the sides lined with 2-inch. In case 
of sand formation, in addition to making the floor perfectly tight, a tight curb- 
ing should be built up with substantial planks around and on the floor to pre- 
vent the sliding of the bank formed by the excavation. This keeps the mill 
foundations safe from undermining and settling. In none of these points 
should the work be slighted. 

The hole for the wheel draft cylinder must be cut through the floor 
(between trimmers) of a diameter one inch larger ihan the cylinder mensure, 



100 SETTING WHEELS, ETC. 

to allow for adjusting wheel. Use extra care to plane off the curb of this 
hole until it is perfectly level, so that the wheel may set exactly level when it 
is in place. Be careful in adjusting the followers at top of dome, so as 
not to get them too tight. They must be set up by the set screws carefully, 
so that the shaft stands perfectly upright and easy. In setting the trans- 
mitting shaft, too much care cannot be exercised in getting it perfectly 
plumb; it should also rest properly in the box above. Notice that the coup- 
ling at the wheel is put together according to the marks made upon it. All 
of the shafting and bearings should he in perfect line. 

There is many a turbine giving poor results and calling forth a spicy cor- 
respondence and wrathy visits between the maker and the buyer, when noth- 
ing but the setting should be held responsible for the low duty or unsatisfac- 
tory performance. Sometimes twin wheels will be sent out to be mounted 
under almost exactly the same circumstances, and one will give a good result 
and the other a bad, especially where there is any liability to change of head. 
One of the most important things to attend to is the wheel pit. 

Areas of Head Race, Flume and Tail Race. — Find out how 
many cubic feet of water per minute are required to produce the required 
power. The forebay leading to the flume should be wide and deep enough 
to let the water pass the wheel no faster than i\ feet per second. There 
should be no abrupt turns or cramped passages to cause eddies, as these 
reduce the working head. The tail race should have the same capacity. 
When possible it should have at least two feet of dead water (three or four 
are better) in its entire length when the wheels are not running. This allows 
the water which comes from the wheel to conform at once to the general level 
of that in the tail race (or the river). Thus no working head is lost. To 
obtain the required area of race in square feet, divide the number of cubic 
feet discharged per minute, by the wheel, by 85; that is, every 85 cubic feet 
of water used per minute by the wheel require one square foot of cross sec- 
tion in all passages to and from the wheel. 

Building Flumes. — Flumes should be built properly. They are gen- 
erally built too light, and by springing and bending loss of water is caused 
by leakage. They are generally made too small to conduct the water to the 
wheels without loss of head. The cross section of the flume should be not 
less than ten times the area of the discharge, and under high heads (say 
50 feet) the area should be twenty times the area of the discharge. The 
spout that conducts the water from the flume or bulkhead should be not less 
than ten times the area of discharge. Thus, if a turbine uses 56 inches of 
water, the spout should have an area of 560 square inches at least. This rule 
is right for straight flumes. Where they make a half turn the area should be 
increased 50 to 100 per cent., as a square bend will often take off nearly half 
of the supply. 

Position of Flumes. — Where turbines are used the flumes may be 
behind and outside of the mill, the water being carried to the wheels by 
openings through the foundation walls. Overshots may also be behind 
the mill, between it and the bank. They may have a spur gear around their 
outer rim on the end next the mill, and from this the main shaft may 



AREAS OF HEAD RACE— BUILDING FLUMES. 



iOl 



be driven by a spur pinion; or, there may be a short shaft bearing a spur 
pinion on the outer end to gear with the large spur, and the inner end 
may bear a bevel wheel driving the upright shaft from which the spindle and 
ston-es are driven, the bolts being driven by a small shaft coupled to the top 
of the upright shaft and extending up through the mill. Sometimes the road 
and the mill yard are upon a bank and the wheel is inside of the mill. 
In such a case there may be a large bevel wheel made up of segments bolted 
upon one end of the wheel, which is made extra stout for this purpose. 

Decked Penstock. — It is frequently the case in flouring mills that the 
flume is so placed that it is difficult to pass the wheel shaft above the 




Fig. 49- — Decked Penstock, 

surface of the water. This happens where the water is on a level with the 
second or third story of the mill and the machinery operating is on the 
first floor. Fig. 49 shows the method of placing the wheel in the horizontal 
off shoot of the flume. The upper deck of this oft" shoot has a stuffing box. 
By this arrangement the power can be brought near to the point where 
the work is to be done, instead of requiring a long train of gears and shaft- 
ing to use up power. In building this style of flume there must be ver)' 



102 



SETTING WHEELS, ETC. 



strong, heavy and closely fitted timbers and jjlanks. The gate rod also 
passes through a stuffing box in the deck. 

Details of Raised Penstock. — In Fig. 50 is shown a very strong 
arrangement of penstock raised ui)on stone i)iers. It will be noticed that the 
intermediate sills supporting the floor of the penstock are hung to the main 
cap by bolts. By this means the main sill does not obstruct the free dis- 
charge of water. The stone piers permit free escape of water in all direc- 
tions, besides making a strong foundation. 




KiG. 50.— Details of Raised Penstock. 



IjOW Falls. — In Fig. 51 is shown a good arrangement where the fall is 
low, the wheel being put in an open penstock and the wheel shaft driving the 
burr spindles direct by a large spur wheel gearing into the spindle pinions. 
The space below for the passage of the water should be large; and the ar- 
rangement of the stone piers should allow this. As the floor of the flume 
holds the weight of the wheel and of the water it should l)e good and sirong. 



PENSTOCKS— LOW FALLS, ETC. 



103 



The short tube from the wheel should dip at least two inches below the water 
in the tail race. 

Wooden Flume for Turbines under Higli Falls. — For heads 
up to 75 feet, the corner posts will not need to be over 6x6 inches. For 40 
feet head, to give enough water for a i7^--inch Victor wheel, the flume would 
have to be 40 inches by 40 in the clear. For the first five feet at the bottom, 
the plank would have to be 4 or 4^ inches thick, then above that 3-inch for 




Fig. 51. — Open Penstock. 



15 feet, then 2-inch would be thick enough as the pressure got less. The 
horizontal flume should be 40 inches wide and 50 or 52 inches deep, allowing 
the water to run at nearly two feet per second. For a wheel using less water, 
the penstock would need to be of less diameter. All of the planks should be 
cut to gauge ; say one-half of them 42 inches and the rest 60 for a 40-inch 
penstock and 4-inch planks. As a 40 x 40 inch penstock, with 40 feet of 
water, weighs 28,160 pounds and has a pressure of 17^ pounds per square 
inch, there nmst be a good, strong foundation, (Fig. 52\ 




Fig. 52.— Wooden Flume for Tirbines under High Falls. 



SIZES FOR WOODEN GRIPES. 



105 



H 
hJ 
O 

o 

en 
W 
N 






H 

O 
(X 

Q 
< 



a w 

Q 

O 
O 

o 

o" 

o 
o 



o 

W 
N 



t> N 

|£ 

^ w 

°: 3 
o 



w 

Q 
O 
O 

O 



o 






X 



W 
O 

Oh ?; 

z 



O 

CO 

U 

pa 



•a 4) 
g o u 

O U 4J 

= c o 

— '^i; 

° c o 



•saijoui ui 'sjjoa JO azig 



kH M W M 



pBOjg qjiM saduf) jo azig 



■S3^3uj UI '3ran[j 
aSpa HJiAi sadijf) jo azig 



xxxxxxxxxxxx 



-irf :c^+ Xt'"- '^ H^ ^ 

vn mo ^o r^ r^ 
X X X X X X 
c^ CO c*~) ^ -si- "^ 



■saqouj ui 'auitujj 
a^pa TjjiAV saduf) jo azig 



r^TI r-t» l-tf* H^ H^ '-*^ ^' '-'^ ^^ H^ 

XXXXXXXXXXXX 



•saijouj u; 'sapig 
l^nbaqifAV sadiig jo aztg 



•)a3jj ni 'sp'EaH 



-f*xf-t -f*KH 3:t»i--*D -^it~t»tct* 



inOmOvriOOOOOOO 
iHi-tcsc^cO'^invOcoO'^ 



OJ <u 

SO 

I- u • 

crH c 
<u o 2 

4, « U 
3 C C 

EJ3 5 






•saijoui UI 's}ioa JO azig 



M M 1-1 M l-H M N 



■auiniji am oj apig 
p-EOJa HJiAv S3dij£) JO azig 



•saijoni UI 'arania 
aqj OJ apis av6jib]\[ jo 
aSpg njiAv sadijg jo azig 



■saqoui UI 'auini >{ 
ai)j oj apig A\djaBf<[ jo 
aSpg ^V.'^ sadug jo azig 



w CO '^ '^l- ^ u^ \ri\D ^o r-^oo o 
XXXXXXXXXXXX 

<x> r^vo r^ o^ r^ c>co 



O O M 



H;i r-^^ ,-(ri ,-4^ kH s^ i^» 

'TT m u-ivo O O r^oo oo o^ c^ O 



XXXXXXXXXXXX 
N « CO CO ^ ^ to ino vQ f^oo 



H^i ^^fx L-:t» ^1 H^' °+0 W^- -H «tJt^ WH O 

CO Tf Tf in invo vO r^ f^oo oo t-i 

XXXXXXXXXXXX 

CO CO -^ "^ vn invo vo t^ r~^oo O 



•saijoui UI 'sapis 
IBtibg HJiMsadiif) jo'aztg 



'^^^^ ut speaH 



CO ^ Tl- u^ IT) »r>vO o r^ r^oo o 



inO^^Ou^OOOOOOO 
>-^-HOIC^co^ir)vOooO"^ 



•sanouj UI sjiog jo azig 



So 

"Si ° S 
o « 5 

N 

(/5 



•aiunij am oj apig 
p'EOJa miA\ sadu£) JO azig 



lr-(«(a) Kfrll L^CO ^|r-t'"^[r-Hr-f+ M^^ r-j?) «H- ^^^^f^ 

M W M M k-( M 01 



co-^u^min'O r^r^cocjo O^O 



XXXXXXXXXXXX 
\0 t^ r^oo cooc>oO'-'W-^ 



■saijouj UI 'auinijj 
auj OJ apig A\djjE^ jo 
aspa qjiM sadu£) jo azig 



-ri H-t-friKt^ -pi t-^ ■r:t30 «t=D kH 
inO f^C30 t^oo CO OO cr» O M 0* 



XXXXXXXXXXXX 

01 cococomino r^r^c30 o^o 



■saqaui ui 'auin|jj 
am OJ apig a\ojjb{<[ jo 
a3pa qji.iA sadu£) jo azig 



•sanauj UI sapig 
[Bnbg njiAA sadiif) jo azig 



•jaa jj ui 'spBaH 



Ht --H ^^' '"^t"^' 'CH K1^ ^-^J H-* 5:H '^J H^: 



XXXXXXXXXXXX 
CO 'd- -^ \n\0 so r^oo oo o O ^ 



t-fx --t?! r-t;i r~}x ,-^1 ,-t» ic|» H^ Hrt kH< 

■^ -^ u->o vO vO r^oo oo (> o '-' 



ir)0"^0ir)O0O0000 
i-» M cj cs CO -r invO CO O "^ 



^■^f 



aj '-^ 
I- w o 

3J= U 

tt< " S 

lOJ^ o 

oDh a, 
.2oO 



•saqauj UI 'sjiog Jo azjg 



•saqouj UI 'aiunj .{ 
am OJ apig avojjbm jo 
aSpg mjM. sadij£) jo azig 



■saqauj ui 'auinia 

am OJ apig AvdjjEf<[ JO 
aspa qjiAV sadijf) jo azig 



'saijauj UI 'sapig 
Iisiiba miA^ saduf) JO azig 



•jaaa «! 'spBafj 



_l» ish-= h-„te 

H M M 
r-tM -pi -tM Kir, -(-1 

O r^oo o^ O O 

M 

X X X X X X 

o r^oo 00 o oi 

X X X X X X 
u-lO O 1^00 CO 

-pir^N-(:oi-^-pi 

mo r^ i^co Oi 



■mOmOmoOOOOOO 
M i-( N c^ CO ^ irt<^ CO O m 



o N 1) c !r ■" 

2 <L> O ^ O y 



vc t: 




U V-, 




.S -^ ■- '5 




»1 ^^ ° 


M « 


3^ — <u Q- 
S? rt boo 


o^ 


C« ■" 


c-aj5 1=^ 


^ll^J 


UJ CS r 



0) 






C^ o 



■o ^ 0) 
-a ■" t; 



J3 o 



0) 



*-- O 1- 
<P >- o 

o c c 



•" -a — O mo. 



T <u 3 ^ 

c 



■a (/5 
o ^ 

- 3 






O 3 



be 



be-; 



; = OJ .i^ i« in 



U .- ^ --. ^ w 

-CI r 2 " « 



a. c T3 



ft'j 



^'bfi'* 



u t; .: 



3 J> ^ C "1 'U 

c3 (u ,j j:: 

C o ^ tn -^ 

r3 V) ci i- _ 



ho o 
C ' 
O 



O t\i 






TO 



n ^ 



c« 



u S "^ "i- 



■^ .r o 

en 3 ^ 

-a '=^>, 

O 13 U 
O O J= 
> O ■" 
7 ho in 
X) c« 



Q, in bo 

?i:= " o 
c > o o 

,q= ht: .£ -U 






(u -w " o <u ^ 
bo3 " 
1- ^ 



"^ CU _^ O 

._ in ho C C 

V- _ L, OJ c ?J _^ 

^ >-a « ^ & ^ 
MMii S^ r ^ « 



^ "^ 'O ^ tn 

in T3 c J^ OJ d) 

iu;S--= « - vS*^ 
w^ O^ J« "-"= 

' • ^ ^ *- O. O .- 
s. w- ^^ '-' lU CO lU 

•- ^ -;: "" >- c 
S — '" o 



<" in . 



lU 



a CU 



^■§ 



'„ 3 



ca 



il N " £ ^ 

,r -s s - =" 

«H j; s o -. - 

c o <D x: 

'■ c - 

O 1) c« J3 



U -C 



in c^ 

O 



SE.B- 



g !« o 



■" i; lu 

1-, S O 

bo-5-c 



« 



106 SETTING WHEELS, ETC. 

The Draft Tube.— This is used where the head is very high or the 
location does not admit of putting the wheel down at the tail water level. In 
theory it may be used up to 30 feet in height; but in practice it is best not to 
use over 20 feet length, because it is difftcult to keep tight. It must have 
sufficient internal diameter to receive the cylinder of the wheel case. If of 
wood, it should run up through the opening in the flume floor flush with the 
face cants on which the wheel case rests. If of iron, it must form a tight 
joint with the wheel case flange. The draft tube is desirable where it is not 
convenient to make deep excavation. All downward and inward discharge 
turbines make use of the draft tube, and these downward discharge wheels 
have the additional advantage of being compact. 

The Rack. — The flume should have a rack to prevent the passage of 
drift wood and other rubbish. A rack of iron bars is best; but if this is not 
used take wooden bars, 3x1 inch, set edgewise and beveled to an edge on 
the up-stream side. Set the bars i inch apart, as a maximum, and at an 
angle of 45 degrees. This rack should be raked out often to keep it clear. 
The bars should be far enough apart not to obstruct the flow of water, and 
should be kept clean of all trash; otherwise many inches of head may be 
lost. It is a good plan to put in a coarse rack several feet above the finer 
rack, this will retain the coarser drift. The spaces in it may be twice as 
large as in the fine. The entire forebay should be covered with boards from 
the last rack towards the wheel and over it ; this is to keep the rubbish from 
dropping or being thrown in the water and getting in the wheel. 

Flood Gates. — Sites and streams subject to freshets are of course 
dangerous. This is the case where the dam and the mill are in a narrow val- 
ley where there is no place for the water to back up in case of a heavy rain 
and spread over a great surface. In such case the dam and foundations 
should be made especially strong. Where there is a scarcity of water and it 
is necessary to keep the head high, flood gates should be used. The smaller 
these are the better. — A small flood gate is made by laying a strong sill at 
low water mark, from which the gate is swung by hinges on the down-stream 
side of the sill. When the gate is closed the lower edge rests upon the sill. 
Slight pressure from the upper side forces the gate over and outward. The 
hinges should be 2-^ inches below the sill top, so that the whole gate, when 
thrown over, will be down below the sill level. To keep the gate from being 
thrown over by a full pond, there is usually a lever supported by a fulcrum 
bolted to the side of the gate and extending up 3 or 4 inches; this fulcrum 
has a notch which holds the lever. The large end sticks up stream 5 or 
6 feet from the fulcrum; and down stream a little over a foot. A piece of 
inch board, about 10 x 12, is attached on the lower side of this lever. Another 
piece of board, 10 x 3, is attached across the end of the lever, and to the side 
of the short board the lever is fastened to the gate by a piece of chain. The 
up-stream end of the lever has a weight sufficiently heavy to hold it down until 
the pressure of water flowing over the flood gate and falling upon the apron 
formed by the two boards on the down-stream side of the lever throws the 
lever over. This brings the gate down. Logs or any kind of rubbish can 
pass it without clogging or injuring it. 



CHAPTER VIII. 

MEASURING WATER POWER. 

Falls — Theoretic Velocity and Discharge — Rules for Measurement by Weirs— Measurement by 
Floats— Stream Power — Work of Water-Wheels by Night and Day. 

If water is used the millwright should know to a pound just how much 
he gets. Simplicity in transmission should be aimed at. There is a good 
deal of foolishness spoken and written on the subject of power and work 
and force, and the meaning of the writers and talkers is generally veiled 
under words to which each gives a different meaning, so that the average 
reader is disgusted with the whole subject, and many men neglect to study 
the laws of power and motion simply from the fact that they tire of the talk 
and nonsense. There is nothing more common sense in this world than the 
science of dynamics. In it a pound means sixteen ounces every time. 
There is nothing more exact possible than its laws. If you put a foot- 
pound of work into a machine there is no earthly means of getting more 
than a foot-pound out of it — there is no earthly means of getting even a full 
foot-pound of work out of it. The nearer we can come to getting a foot- 
pound out of it by reducing the friction, the better we shall have succeeded 
in utilizing it ; but we cannot expect to improve upon or change the law 
which controls it. 

Fall of Water. — A very slight declivity suffices to give a running 
motion to water. Three inches per mile, in a smooth, straight channel, gives 
a velocity of about three miles an hour. The Ganges, which gathers the 
waters of the Himalaya Mountains, the loftiest in the world, is, at i8o miles 
from its mouth, only 800 feet above the level of the sea, and to fall these 
800 feet, in the long course of the water, requires more than a month. 

Theoretic Velocity and Discharge. — The following table shows 
the theoretical spouting velocity of water in feet per second, and number of 
cubic feet discharged per minute, through an orifice of one inch area, under 
different heads, from one to forty feet, (calculated from Francis' formulas). 
The table represents the theoretic velocity and discharge due to an orifice 
conformed in all respects to the shape of the contracted vein. In ordi- 
nary practice, through orifices having parallel sides, the actual velocity 
and discharge will be about 64 per cent, of the table. Bearing this fact in 
mind, the above table may be used with reasonable accuracy in measuring 
the discharge of water through ordinary gate openings onto overshot and 
breast wheels, through waste gates, or other apertures cut in plank. Exam- 
ple : Suppose the opening through which the water passes onto an overshot 



108 



MEASURING WATER POWER. 



wheel to be 72 inches long, and the gate to be hoisted 2 inches, what amount 
of water will it discharge per minute, with three feet head of water in the 
forebay above the opening? Solution: 72" x 2 =144 square inches x 5.78 
(the discharge stated in table for an orifice of one inch area under three feet 
head) — 832 cubic feet, theoretic discharge per minute; 64 per cent, of which 
= 532 cubic feet, (r<-///rt'/ discharge per minute. There are many instances in 
powers already improved where the quantity of water in a stream can be 
ascertained, by using the above table, without resorting to measurement by 
weir. In ascertaining the head of water under which an orifice is discharg- 
ing, measure from the surface of the water to the centre of the orifice. 

TABLE SHOWING THEORETIC VELOCITY AND DISCHARGE. 







4) . 









1 1 

en 




1 

4> . 


Min- 
Ori- 
h. 




C/3 *-» 


h^t; 




C/3 V. 


I- -*■• 




Ol -M 


w^ 






<u J5 


fc. 




u £ 
a1 OJ tu 






£ c 


c 


>>.s 




c 


^B 




c 


>..s 


fc^O 


TS' 


'S'<= 


ajaj 


-a 


■5^3- 


rtTu 


-a 


oxT 


l' u 


0) 


S. c 
oj 


s=.^ 




.2 c 

4J 


--•So 
■2 3"C 




c 
a> 


■2 =« 


K 


> 


;3 




X 


> 


;3 


E 


> 


3 


I 


8.02 


3-34 


15 


31.06 


12.94 


28 


42.43 


17.68 


2 


11-34 


4-73 


16 


32.08 


13.36 


29 


43-19 


17.98 


3 


13.89 


5-78 


17 


33 c6 


13-77 


30 


43 93 


18.30 


4 


16.04 


6.68 


18 


34.02 


14.18 


31 


44-65 


18.60 


5 


17-93 


7-47 


19 


3496 


14-57 


32 


45-37 


18. go 


6 


19-64 


8.18 


20 


35-S7 


14.94 


33 


46.07 


• 19.20 


7 


21.22 


8.84 


21 


36.75 


15-31 


34 


46.76 


19.48 


8 


22.68 


9-45 


22 


37.62 


15.66 


35 


47-45 


19.76 


9 


24.06 


10.02 


23 


38.46 


16.02 


36 


48.12 


20.05 


10 


25-36 


10.57 


24 


39.29 


16.36 


37 


48.78 


20.33 


II 


26.60 


11.08 


25 


40.10 


16.71 


38 


49-44 


20. 6 u 


12 


27.78 


11-57 


26 


40. Sg 


17-04 


39 


50.08 


20.87 


13 


28.91 


12.05 


27 


41.67 


17.36 


40 


50.72 


21.13 


14 


30.00 


12.49 















Measurement by Weirs. — Where the stream is sufificiently narrow, 
the simplest mode of measurement is to make a weir by taking a board long 
and wide enough to make a dam across the stream. Cut a notch in the upper 
edge of the board deep enough to pass all the water to be measured, but not 
longer than two-thirds of the width of the stream. Bevel the bottom and 
both ends of the weir, on the down-stream side, to within an eighth of an 
inch of the up-stream side of the board, leaving the edge or crest almost 
sharp, and perfectly level. Drive a stake in the bottom of the stream, a few 
feet back of the weir, its top exactly level with the crest of the weir. When 
the water has reached its greatest depth, measure with the square the depth 
above the top of the stake, and this measurement will indicate the true depth 
of the water upon the crest of the weir (Fig. 53). The amount of water the 
stream furnishes can now be computed from the subjoined table for weirs. 
The table for weirs gives the number of cubic feet per minute that will 
pass over a weir one inch wide, and from one inch to eighteen and se\en- 
eighths inches deep. The column marked " Inches depth on weir" indicates 
the depth of water flowing over the weir, and the second column, under o, gives 



MEASUREMENT BY WEIRS. 



109 



the number of cubic feet per minute for the even inches in depth. In the third 
column, under one-eighth, is the amount of the second coUimn, with the ad- 




ditional amount due to the additional one-eighth inch in depth added, and so 
on across the table from left to right. By multiplying the number of cubic 



iin 



MEASURING WATER POWER. 



feet that one inch in width will discharge, as stated in table, by the width of 
the weir in inches, the result will be the total discharge of weir per minute. 
The depth on the weir should be measured at a ])oint just back of where the 
curve on the surface of the water commences. 

Where the stream is too large to measure by a weir, choose some place in 
it where there is a moderate current or a smooth flow, and measure its 
velocity by a float ; measure its width and average depth, and then from 
the hydraulic tables published in many books the flow can be measured. 

TABLE FOR WEIRS. 



InchesDepth 
on 





y^ 


Ya 


y% 


y 


% 


% 


n 


Weir. 


















I 


0.40 


0.41 


0.56 


0.65 


0-74 


0.83 


0.97 


1-03 


2 


1. 14 


1-25 


1.36 


1.47 


1-59 


1.71 


1.84 


1.96 


3 


2.09 


2.12 


2.36 


2.60 


2.64 


2.78 


2-93 


3.06 


4 


3.22 


3.38 


3-53 


3-69 


3.85 


4.01 


4.17 


4-35 


5 


4-51 


4.68 


4.85 


5.02 


5 20 


5-38 


5-56 


5-74 


6 


592 


6.10 


6.30 


6.49 


6.68 


6.87 


7.07 


7-27 


7 


7.46 


7.67 


7.87 


8.07 


8.28 


8.49 


8.70 


8.91 


. 8 


9.12 


9-33 


9-55 


9-77 


9-99 


10.21 


10.43 


10.66 


9 


10.88 


II. II 


"•34 


11-57 


11.80 


12.04 


12.27 


12.51 


10 


12.75 


1315 


1323 


13-47 


13.72 


13.96 


14.21 


14.46 


II 


14.71 


14.96 


15.21 


15.46 


15.72 


15.98 


16.24 


16.49 


12 


16.76 


17.02 


17.28 


17-55 


17.82 


18.08 


18.35 


1.8.62 


13 


18.89 


19.17 


19.44 


19.72 


20.00 


20.27 


20.56 


20.83 


14 


21.12 


21.40 


21.68 


21.97 


22.26 


22.55 


22.83 


23-13 


15 


23.42 


23.71 


24.01 


24.30 


24.60 


24.90 


25-19 


25-50 


i6 


25.80 


26.10 


26.41 


26.71 


27.02 


27.32 


27.63 


27.94 


17 


28.26 


28.57 


28.88 


29.19 


29-51 


27.83 


30 14 


30.46 


iS 


30.78 


31 II 


31-43 


31-75 


32.07 


32.40 


32-73 


3305 



Measurements by Floats. — The speed of the surface of a stream is 
greater than that of the stream as a body. The surface velocity is readily 
found by means of a piece of floating wood. From this the real velocity of 
the stream may be found by dividing 7.71 plus the surface velocity by 10.25 
plus the surface velocity, and multiplying the quotient by the surface ve- 
locity. This may be expressed by a formula : Real velocity, 



Y=v. 



7.714.V 
10.25-1-V 



Thus if we have a creek of thirty feet mean width, and four feet mean 
depth, with a surface velocity of one foot per second, we have for the real 
velocity of the water : 

. 7-71+1 

j[ X = 0.774 feet. 

10.25+1 

The volume of water which flows through it in a second will be 30 x 4 x 0.774 
= about 92.88 cubic feet, 92.88 x 62.5 = 5,805 pounds flowing every second. 



MEASUREMENTS BY FLOATS—STREAM POWER. 



Ill 



If there is a fall of ten feet there will be 5,805 x 10 = 58,050 foot-pounds 

of power per second, or 58,050 x 60 = 3,483,000 minute foot-pounds ; equal to 

348300 

=105.55 H.P. 

33000 

The gross power of the fall is measured by the product of its height by 
the weight of water passing. This product is 550 foot-pounds per second 
per horse-power. With an efficiency of 0.7, it takes 785.7 foot-pounds per 
second per horse-power ; that is, under these circumstances, with one foot 
fall, 12.6 cubic feet of water per second will give one horse-power net. With 




, Fig. 54. 

a fall of 100.8 feet, one-eighth of a cubic foot per second, or 7.5 per minute, 
would give one horse-power. 

Stream Power. — To find the exact fall of a stream take two staves, 
graduated in inches and in tenths, and from four to six feet long, also a 
water level ; then (supposing F to be the source and E the discharge) 
order one assistant to the source F with the staff placed perpendicular. Send 
another assistant to any convenient place, as A, with his staff perpendicular. 
Then place the water level in the centre, as at W; then order the first assist- 
ant at F to move a piece of white paper up and down on his staff until you 




Fig. 55. 



J 
I 



can see it through the level. Let him then know the distance of the paper 
from the ground, and do the same thing at the other end of the level with 
the other assistant at A ; then send the first assistant to A, and the second to 
some new place, as B, replace the level and proceed as before, and so on 
until the second assistant arrives at E ; then add all the notes of the first 
assistant together, and those of the second, and the difference between the 
two sums will be the difference in level between the two extreme stations.* 

* On long runs there should be an allowance for the curvature of the earth's surface. 



112 MEASURING WATER POWER. 

To nicasLire the width of a river without actually going across it : Sup- 
pose A B be the line of survey, striking the river bank at B. Mark some 
tree or bush on the opposite bank, in line with A B, then lay off some con- 
venient number of feet from B to D, at right angles to the line A B, from 
D to E lay off the same distance as from B to 1) ; then walk from E, at 
right angles to B E, and parallel with A B, until you reach the point F, 
which is in line with the points C and D ; then measure from E to F, which 
will be the same distance as from B to C, or the width of the stream. 
The following is taken from the Paper Trade Journal : 
Work of Water- Wheels by Night and Day. — An editorial para- 
graph appeared in a Western ])aper a short time ago in reference to the 
work of water-wheels by night and day. The assertion, too, has often been 
made that water-wheels do more work in the night than during the day. Of 
course there must be a fallacy in such an assertion. Many assert that there 
is an increase in the velocity by the air's becoming heavier after sunset. This 
is another fallacy. The subject comes up about once in every dozen years, 
and has as much periodical vitality as " perpetual motion." The truth of 
the matter can be easily demonstrated at any time by experiments. Many 
assert that a change in the moon produces a change in the weather, and this 
assertion has some foundation in truth; but how can it affect the wheel, and 
if the pressure of air is greater upon the water at night than in the day, it 
would obstruct the flow of water as much as it would tend to increase it, and 
even more particularly if the fall was high, because the increase of pressure 
near the earth would exceed the increase at a greater altitude. ' The advo- 
cates of the theory that water wheels run faster by night than by day have 
simply observed the wheels by the eye in the loosest manner possible, without 
measuring either the velocity of the wheel or the varying head of the water. 
A correspondent of the Journal some years ago made a test in order to settle 
the question. He used a very perfect apparatus for testing water-wheels, 
and observed their performance for several successive days and nights. He 
made five experiments in the middle of the day, and three in the middle of 
the night, on a wheel eighteen inches in diameter, running without resistance 
under a fall (H) of eight and more feet, running the wheel at 2,000 revolu- 
tions at each experiment, the time being calculated by noting the seconds for 
every 100 revolutions by a bell hammer attached to the wheel shaft. The 
following were the results of each experiment under the fall (H), which actu- 
ated the wheel, in revolutions per second. The revolutions are then reduced 
to what they would have been had the fall (H) been the same in every ex- 
periment, having one in each series, night and day, equal to 8.41' feet. R is 
reduced to that H by the formula, as 

V' H : R = ^/ 8.41' : : R' 

DAY EXTERIMENTS. 

H. Revolutions. H'. R' . 

8.410 feet 4,901960 8.41 feet 4.90196 

8.515 feet 4.962230 8.41 feet 4-93144 

8.290 feet 4-889975 8.41 feet 4-O2524 

8.422 feet 4.926108 8.41 feet 4.92260 

8.42 [6 feet 4.950544 8 41 feet 4 94713 

Mean revolutions, 4.92569. 



WORK OF WATER-WHEELS BY NIGHT AND DAY. 113 

NIGHT EXPERIMENTS. 
H. Revolutions. H' . R' . 

8.41 feet 4.88997 8.41 feet 4.8S997 

8.61 feet 4.98753 8.41 feet 4.93947 

8.42 feet 4.93S27 8. 41 feet 4-93553 

Mean revolutions, 4.92159 ; the temperature of the water being the same. 

On comparing the results of the two scries of experiments, it will be seen 
that there is a slight difference in favor of the wheel's revolutions in the day. 
A careful test such as this is worth all the speculation that could be entered 
into by theorists whose minds are prejudiced in favor of one side, and who 
generally come to a conclusion before they commence to investigate. The 
combined influence of the sun and moon is only sufficient to produce the 
rise in the ocean known as the tide; and even allowing for its extreme height 
on shores the peculiar conformation of which concentrates, so to speak, the 
force otherwise spread over a large surface, the total rise is hardly to be 
appreciated when considered with reference to the bulk of the earth. The 
startling fact was announced some few years ago that the discovery was 
made that a little less than one-third of an inch rise had been detected on 
Lake Erie. If only one-third of an inch of a rise takes place on so large a 
body of water, how much would the tide of a mill pond affect the running of 
a water-wheel ? The theory that a water-wheel does more work by night 
than by day is, therefore, not in accordance with the facts. 



^4=1^ 



CHAPTER IX. 

BOILERS. 

Combustion— Fuels— Waste of Fuel— Material for Boilers— Effects of Heating— Testing Plate— Boiler 
Shapes— Laterally Fired Horizontal Boilers— Internal Firing— Tubular— Water Tubes— Elephant 
—Proportions— Draft Area of Tubes— Steam Room— Weakening Effects of Common Steam 
Domes — Flues and Tubes— Grate Bars -Setting — Smoke Consumers — Chimneys^Cowls— Steam 
Pipe— Dry Pipe— Safety Valves— Fusible Plugs— Pressure Gauges— Glass Water Gauge— Draft 
Regulator — Feed Pipe — Feed Pump — Injector — Steam Traps — Blow-Off Valve — Blowers — 
Heating and Filtering Feed Water— Corrosion, External, Internal— Grooving — Incrustation- 
Character of Scale— Scale Preventatives — Management, 

Combustion. — Combustion is the rapid combination of oxygen with 
carbon or hydrogen, and is always attended with evolution of heat. Flame 
is the gas or vapor which passes off during combustion, its surface burning 
with the emission of light, by reason of the more perfect oxidation of the 
carbon contained in the fuel. Hydrogen burns with a very faint blue flame. 
Carbon when burning should be oxidized completely into carbonic acid; if 
only partly oxidized it forms carbonic oxide. Only experienced persons can 
tell the nature of a flame by its color, or even tell its color accurately in the 
moment of introducing fuel. Net combustion means the pounds of fuel burn- 
ed after deducting the ashes and other non-combustible material. Available 
heat is that part of the heat of combustion which is given up to the water in 
the steam boiler. By " furnace " is meant the whole apparatus for burning fuel 
and transferring heat to the water in the boiler, and it includes ash pan, air 
holes, flame chamber, flues, tubes, heating surface, and chimney. The air is 
made up of about seventy-nine volumes of nitrogen and about twenty-one 
of oxygen, together with a little watery vapor, and .0003 to .001 volumes of 
carbonic acid. One cubic foot of air, at 32° F., weighs .080728 pounds, or 
565.1 grains; at 62° F., .076097 pounds, or 532.7 grains. One pound of air, 
at 32° F., takes up 12.4 cubic feet. Nitrogen neither burns nor supports 
combustion, but simply dilutes the oxygen in the air. 

The gases of combustion are com]>osed principally of carbonic acid, car- 
bonic oxide, nitrogen, unconsumed air, and steam. One pound of carbon is 
combined with two and sixty-seven hundredths (2.67) pounds of oxygen to 
form three and sixty-seven hundredths (3.67) pounds of carbonic acid, and 
would be accompanied by eight and ninety-four hundredths (8.94) pounds of 
nitrogen left after the separation of the oxygen from the air. Total, twelve 
and sixty-one hundredths (12.61.) jjounds. The specific heat of carbonic acid 
being .2164 and that of nitrogen .244, we have as the number of heat units 
absorbed in raising the gases from the combustion of one pound carbon : 

Carbonic acid 3.67 X 2.2164, .794 heat units. 

Nitrogen, 8.94 X .244, 2.1S1 

Total, 2.975 



COMBUSTION. 115 

As the total heat of the combustion of one pound of carbon is 14544 
heat units, we have 

14544 

= 4889' F. 

2.975 

as the highest theoretical temperature to be got by the complete combustion 
of one pound of carbon. This is allowing 11. 61 pounds of air to one pound 
of carbon, which is the least possible amount of air. Allowing eighteen 
pounds of air instead of twelve pounds we shall have: 

Carbon, . - 1. 00 pounds. 

Oxygen, 2.67 " 

Nitrogen, . . . . . . . . . 8.94 " 

Air unconsumed, . . . . . . . . 6.39 " 

Total, .......... 19.00 " 

The products will absorb heat units as follows: 

Carbonic acid 3.67 lbs. x .2164 ^ .794 Heat units. 

Nitrogen 8.94 " x .2440 = 2.181 " 

Uncombined, .... 6.39 " x .2377 = 1.519 " 

Totals, ..... ig.oo " 4-494 " 

The highest theoretical temperature would be 

14544 

= 3236 F., 

4-494 

or 33.81 per cent, less than when there was no excess of air admitted. If 
double the quantity of air be admitted, the temperature will be only 2450°. 

One pound of hydrogen takes eight pounds of oxygen to burn it com- 
pletely, and this requires thirty-six pounds of air to furnish it; forming nine 
pounds of water and setting free twenty-eight pounds of nitrogen. One 
pound of pure carbon takes two and two-thirds pounds of oxygen to burn it 
completely, taking twelve pounds of air and producing three and two-thirds 
pounds of carbonic acid. If this same pound of carbon be incompletely 
burned, that is, only to carbonic oxide, instead of completely to carbonic 
acid, it will consume only one and one-third pounds of oxygen, and take 
only six pounds of air. One pound of wood charcoal takes 11.16 pounds 
of air to burn it completely; good coke, 11.28 pounds; anthracite coal, 12.13; 
dry bituminous coal, 12.6; caking coal, 10.581011. 73; dry, long flaming coal, 
10.32; lignite, 9.30; dry peat, 7.68; dry wood, 6. Losses in combustion 
take place from many causes. That of radiation from the sides of the fur- 
nace may be very largely prevented by double hollow walls. That bv the 
use of cold air, as fed in place of hot, may be prevented in part by forcing 
the air through the hollow space between the double walls. There is a loss 
due to the escaping gases' being at a lower temperature than the surrounding 
air at the mouth of the chimney. This may be largely done away with by 
using a forced draft. The loss by unburned fuel passing through the grates 
and off through the chimney as smoke we shall not here consider, nor that 
by imperfect combustion. One advantage of heating air for furnace supply 
is that it acts as a corrective when too much or too little air is admitted- 







4 






10 


12 


to 


iG 


15 


to 


24 


20 


to 


23 


24 


to 


27 


40 


to 


120 



11(5 BOILERS. 

Further, the affinity of carbon for heated air is greater than that for cold, 
and the combustion is more concentrated. There is no use in having com- 
bustion take place if the gases have gone beyond the spot where they can 
impart heat to the water in the boiler. There is a great saving by heating 
the air of combustion by means of the gases that have passed beyond the 
heating surface of the boiler. This saving largely results from heating the 
nitrogen of the air before it gets to the fire chamber, and thus preventing it 
from absorbing heat there. If, instead of the twelve pounds of air necessary 
to the combustion of one pound of coal, we let in twenty-four, there should 
result 3f pounds of carbonic acid and 2if pounds of nitrogen; which last 
would take up 2if x.245 =5-3o8 heat units, and reduce the theoretical 
highest temperature to 2440°. 

Different boilers burn different quantities of coal per hour per square 
foot of grate. The rate of combustion depends upon the coal, the grate, the 
flue and the draft. English coals, with chimney draft, burn about as follows 
per square foot per hour: 

Cornish boilers, slowest rate, ..... 

Cornish boilers, ordinarj' rate, ..... 

Factory boilers, ordinary, ...... 

Marine boilers, ordinar}^ ...... 

Dry coal, quickest rate, air coming through grate only . 
Caking coal, air holes above the grate, 1-36 the grate area 
Locomotives, . . . . . . . . . -40 

Ordinarily, one pound of coal evaporates from six to ten pounds of water 
from and at 212°, ten pounds being about seventy-one per cent, of the 
theoretical evaporative power of good coal or coke. 

Fuels. — The various fuels used are wood, peat and coal; the latter 
being divided into lignite, bituminous and anthracite, and the bituminous 
subdivided into (i) non-caking, rich in carbon; (2) caking, and (3) non-cak- 
ing, rich in oxygen. There are two general classes of wood — hard and soft; 
the hard including oak, hickory, beech, elm, ash and walnut; the soft being 
pine, birch, poplar and willow. Freshly cut wood contains about 45 per 
cent, of moisture; dry wood, so called, about 15 to 20 per cent. Peat is 
half-formed coal. There is a great deal of it in this country, especially in 
Indiana. The darker it is, the richer it is in carbon. It contains about 
75 per cent, of water as a mininum. Lignite stands between peat and coal. 
It can be coked, but the coke is not good. Its heating power is low; it does 
not cake in the fire; it contains 10 to 20 per cent, of water. It is not much 
used in this country, although there is much of it in the far West. Anthra- 
cite coals are either hard or semi-anthracite (gaseous). Hard anthracite is 
slow to kindle and difficult to quench, and burns with an intense heat. It is 
smokeless and burns with a short, blue, transparent flame. It is the king of 
coals, but needs plenty of air. Taking up but little room, it is, where 
obtainable, the favorite for marine purposes. The " Buck Mountain " and 
Harleigh Lehigh anthracites are the finest for steaming, and are generally 
selected for use in competitive tests. Scranton coals are softer and less 
pure. Most' coal in this country is bituminous. While it contains less 



FUELS. 



117 



carbon than anthracite, it has much valuable matter rich in hydrocarbons, 
which give it almost equal heating power with anthracite. Bituminous coals 
proper are divided into caking, cherry and splint. There are also semi- 
bituminous, cherry and splint. There are some highly bituminous coals 
which are really hydrogenous or gas coals; these being divided into cannel, 
hydrogenous, shaly and asphaltic. Bituminous coals contain about i8 to 
20 per cent, of valuable combustible material. The word " bituminous " is a 
misnomer, as true bitumens have no organic structure. Caking coal when 
heated in the furnace swells and fuses together, seems pasty and exudes 
gummy matter, and burns with a bright yellow or red flame with much 
smoke. It forms a cake over the surface of the grate. Block coal is non- 
caking and is very firm, so that it bears transportation; it is sometimes called 
free burning. Semi-bituminous coal has in part the free-burning character 
of the bituminous and freedom from smoke of the anthracite, besides being 
more readily regulated in burning than the anthracite. It kindles freely. 
The energy that is stored up in a pound of coal would raise 11,194,000 
pounds one foot high in a minute. 

One kind of wood is just as good as another when both are equally dry; 
of course, those woods which are dry and close are of more value by the cord 
than those which are porous and which contain large quantities of water. 
The very best kind of wood for steam and heating purposes is shellbark 
hickory, and the next best, white oak. These are followed by red heart 
hickory, red oak, beech, hard maple. Southern and Virginia pine, spruce, and 
New Jersey yellow and white pines. The following table gives the relative 
values of these woods per cord, and their weight in pounds per cord of 128 
cubic feet : 



Variety. 


VS^eight 
in Pounds 
per Cord. 


Relative 
Heating 
Value. 


1 

Variety. 


Weight 
in Pounds 
per Cord. 


Relative 

Heating 

Value. 


White pine.... 
Yellow pine .... 
New Jersey pine 
Spruce 


1,868 
r.goo 
2,137 
2,325 
2,680 
2,878 


1. 000 


Beech 


3,126 
3,254 
3.375 
3,705 
3,821 
4.469 


1.673 

I 741 
1.806 
1.875 
2.045 
2.392 


i.oig 
1. 144 
1.244 
1.434 
1.540 


Red oak 

[ Southern pine. . . . 
Red heart hickory 
White oak 

j Shellbark hickory 


Virginia pine. . . 
Hard maple 



It is a mistaken idea to suppose that the temperature of the fire from one 
kind of fuel is really much higher than that with another fuel; if the con- 
ditions are the same there is, of course, some difference, but not nearly as 
much as is generally imagined. 

Waste of Fuel. — Fuel is wasted in different ways. If mixed with 
foreign matter, that is, with slate, dirt, &c., this dead incombustible matter 
must be heated by the good matter, and this heat is wasted. If this incom- 
bustible matter is fusible, it melts and fills up the air spaces between the 
grate bars and between the lumps of coal (if coal is burned). If the fuel, 
whether coal or wood, is moist, heat will be wasted by being absorbed in 
evaporating this water. Hard anthracite is the driest. Wood contains 
thirty to forty per cent, of water when green, and coke, although made at 



118 BOILERS. 

a high heat, is so porous that it absorbs water from the air, sometimes as 
much as twenty per cent. Fuel is wasted by not being burned at all. 
Sometimes this is the fault of the fireman and sometimes that of the fuel. 
Some coal splits and flies to small pieces; some falls apart, and these 
pieces fall through the grate. A careless fireman will waste fuel by too 
thick or too thin firing; by irregular stoking, (X:c. Fuel may be wasted by 
too much air being admitted into the furnace. This is often caused by 
having too large calorimeter, (cross area of the passage over the bridge wall 
or through the tubes). Whether admitted above or below the grate, the 
air should be supplied in thin, fine streams. Where the bed of fuel is not 
too thin upon the grate, nor unevenly distributed, there is less trouble from 
this cause. 

But, with almost every kind of boiler setting, it is necessary to open the 
fire door for the purpose of slicing or feeding the fire; and this causes the 
entrance of large volumes of cold air, which chill the combustion chamber, 
doing damages in three ways — -by diluting the gases of combustion, by 
cooling the combustion chambers by reason of their low temperature, and 
by causing sudden contraction of the sheets near the door. With artificial 
draft it is better to have smaller lumps of coal, so that the air currents will 
enter more irregularly, and it is better also to have a thicker bed of coal. 
Self-stoking devices lessen the three last named evils. So do rocking 
grates, which enable slicing with open doors to be dispensed with. There 
is much more coal wasted by falling through the grate into the ash pit 
than one would think. This loss is generally greatest with anthracite, 
being in that case nearly twenty per cent. With bituminous- lumps it is less 
than with bituminous dust, being nearly fifteen per cent, in the latter case 
and only about eleven per cent, in the former. 

One of the greatest causes of waste is imperfect combustion. This 
varies greatly with the fuel, the boiler, the grate and the stoker. Less loss 
arises from this with coke, hard anthracite and other fuels containing little 
hydrogen, than with bituminous coals. With tht^ former it is only requisite 
to proportion the thickness of the bed of coals to the velocity of the draft, 
and to supplement the oxidizing action of the air which enters below the 
grates, by thin jets above fhe bed of coals. In the case of the soft bitumi- 
nous coals, sometimes only the thickest portion of the carbon is consumed, 
all of the rest distilling off and passing away without being consumed. In 
this case either smoke or soot is formed. There are remedies for smoke 
which cause waste of fuel rather than saving of it. The fault of these is 
that they simply keep the smoke at a high temperature, from which cause 
the carbonic acid of complete combustion of the thickest carbon of tlie 
fuel is, by admixture with this red hot smoke, reduced to carbonic oxide. 
Every pound of good coal has in it about five and a half horse-powers; but 
in practice we think that we are doing well if we get one horse-power with 
two and a half pounds of coal, that is, if one jiound of coal gives four- 
tenths horse-power, that is, four-fifty-fifths of what it ought to give. 

Never slice the fires as long as the ash pit remains bright. Bituminous 
coal should be sliced from above ; anthracite should never be disturbed on 



MATERIAL FOR BOILERS. 119 

its upper surface. If there are two furnaces they should not be fired at the 
same time. Anthracite coal requires less firing than bituminous. It pays to 
have a good fireman and engineer. In one case on record there was a fire- 
man and engineer combined to run a seventy-five horse-power engine, at $35 
per month. The coal bill was for 136 tons per month, costing $544, or 
about $18 per day. The next man that had the mill ran it with more 
machinery upon one-fourth less fuel, having an engineer at l6o and a 
fireman at $30. 

Material for Boilers. — While the engines of to-day are generally 
good, most boilers are imperfect and unsatisfactory. The pressures 
employed are greatly increasing, having gone from 10 pounds above atmos- 
phere to 100 and even 125 pounds as a regular thing. Boilers maybe of 
cast iron, wrought iron, steel or copper. The latter is not much used, as it 
is expensive, soft and weak. Cast-iron boilers are of necessity of the "sec- 
tional " type. Their advantages over wrought-iron are that cast-iron is the 
better conductor, is more durable, resists corrosion better (being proof 
against chemical action of feed water and gases), does not blister, is less 
easily strained by unequal temperature, requires no braces, resists high 
pressures, is cheap, is easily duplicated, and mended parts are as strong as 
new. The objections raised are that it is treacherous at high or unequal 
temperatures, has hidden flaws that give no warning of weakness, is some- 
what difficult to get uniform in strength, and boilers made of it prime and 
are deficient in circulation. The nearer spherical the parts of a cast-iron 
boiler are the better. 

For wrought-iron boilers, the boiler plates should be strong, tough, hard, 
tenacious, ductile, and easily flanged and welded. Only the best iron should 
be used. The best is " C. H. No. i Flange," with a tensile strength of not less 
than 50,000 pounds to the square inch. Mild steel homogeneous iron or ingot 
iron is now growing in demand. It is homogeneous, strong, malleable, and free 
from laminations and blisters, but is more difficult to work than iron. When 
not properly made it is subject to brittleness, low ductility and cavities. 
Steel boilers should have drilled rather than punched holes ; where they 
have punched ones they should be either annealed or reamed. Iron boiler 
plates should be subjected to a bending test — bending a two-inch strip double, 
cold, until the sides touch. Steel plates should be heated red, then 
quenched in water, and bent over double until the diameter of the inner 
curve is two or three times the thickness of the plate. The driving test 
consists in punching holes, then driving them out larger with a taper punch; 
the larger the holes will stretch out the better the plates. The tensile 
strength of iron plates should be not less than 45,000 pounds per square 
inch, as^shown by strips of uniform cross section, free from nicks and cen- 
trally torn. The tensile strength of steel for boiler plates should not greatly 
exceed 60,000 pounds per square inch; above 70,000 pounds the plates 
are apt to be brittle; below 50,000 pounds they are likely to be spongy. No 
plate should be used which, after heating to a cherry red and plunging into 
cold water, will not allow bending over cold until the sides touch, and with- 
out breaking. 



120 BOILERS. 

Steel boiler plates which have shown high elastic strength and ductile 
extension, when tested in strips before being built up into boilers, some- 
times fracture in different directions. This is possible, because after being 
made the plate has been laid down on a flat surface to cool and having 
cooled more quickly at the edges than in the middle, and this puts a tensile 
strain upon the sheet, the outer parts being in tension first and afterwards in 
compression. 

The only safe way to get reliable boiler iron is to buy plates bearing the 
private stamp of a reliable mill as well as the designation of the grade. 
Those who order boilers would do well to remember this fact. 

Material. — About a dozen years ago Bessemer metal was offered for 
bridge and ship construction, which in the testing machine showed an ulti- 
mate tensile strength of from thirty to forty tons per square inch; an elastic 
limit from twenty to twenty-three tons, and a range of ductile extension of 
from 10 to 1 8 per cent., while the tests of plates considered suitable 
for the shells or barrels of boilers showed figures not much lower than 
these. The failures which occasionally attend the application of this steel, 
however, discouraged the extension of its application by engineers, who 
hoped that greater uniformity in the mechanical jjroperties of the metal 
would gradually be obtained by the steel makers. A steel of somewhat 
lower tenacity and greater ductility, attended by greater uniformity in 
composition and behavior, was then produced, and this indicated that steel 
makers and engineers must look to steel of milder character for the 
removal of the difficulties which had attended the structural application of 
cheap steels, that is, steels not produced by the crucible. The result of this 
was that engineers specifying steel for, say, bridge work, stipulated that it 
should not possess more than a certain maximum tenacity — a reversal of the 
stipulation that had always and does obtain with respect to iron. As a 
further result of this, and to insure that the harder steels, of comparatively 
high tenacity but less certain character, should not be used in the con- 
struction of bridges, the Board of Trade regulations upon the subject 
limited the tensile strain on any part of a structure to seven tons per square 
inch. This has led to the endeavor on the part of all steel makers to 
produce the very mild soft steels now largely used, some of which afford the 
engineer no help toward producing the lighter structures which a dozen 
years ago it was promised that steel would give them. Boiler shells must 
be made nearly or quite as thick as if they were constructed of iron. 

Eflfect of Heating on Plates. — As the temperature is raised, iron 
boiler plates increase in tensile strength until they have a temperature of 
570° F. After this they weaken as the temperature rises. Thus, if a plate 
has a tensile strength of 66,500 pounds at a temperature of 570° F., it will 
have only 56,000 pounds per square inch from 80° down to 32°, and about 
the same at 720 , but at 1,050° its tensile strength will be lessened by nearly 
one-half, being only 32,000 pounds. At 1,240° the tensile strength is only 
one-third of the maximum, being 22,000 pounds; at 1,317° it is only 9,000 
pounds, or only about one-seventh of the maximum. Ordinary boiler plates 
are 6 per cent, stronger in the direction of the fiber than across the grain. 



TESTING PLATES— BOILER SHAPES. 121 

The more the plates are piled and welded in the making the stronger they 
become in every direction. 

Testing Plates. — To sound a boiler plate to see whether it is strong 
and even in quality, line it out into squares of about one foot each; strike 
each square separately a few blows with a light hammer, marking each 
square as struck, so that you will not strike the same square twice. Where 
the plate is good the hammer blows will sound clear and strike heavily ; but 
if there be blisters the sound will be dull and the hammer will rebound. 
Both sides should be tested in this way, as sometimes a plate will test well 
on one side and show a defect on the other. 

Boiler Shapes. — Boiler shells are either cylindrical or rectangular, 
or both combined. Each of these types has its advantages and disadvan- 
tages. 

Rectangular shells have the advantages that they stow well away in the 
hold of a vessel, and in them the furnaces, tubes, flues, connections and 
spaces for steam and water can be better arranged than in cylindrical 
boilers. This is, of course, for marine boilers only. The rectangular shell 
is inferior to the cjlindrical in strength and in simplicity of construction. 

The cylindrical form does not so well adapt itself to the surroundings, 
the steam space is proportionally less for a given height of boiler, and there 
is l^ss air and water surface from which the steam may be disengaged. The 
smaller the boiler the less advantageous the cylindrical form becomes; 
besides Which, there must be more boilers for a given steam capacity, and 
this necessitates extra cost for attachments, connections, etc. 

In some English naval vessels the boilers are partly oval or elliptical in 
cross section, have the larger diameter of the oval placed vertically and having 
cylindrical furnaces. These give larger and higher steam space for a given 
grate surface. 

Vertical fire tube boilers with cylindrical shells have a very high rate of 
combustion, but low duty. This is because vertical heating surface is of less 
value in boilers than horizontal for two reasons : In the first place, if steam 
is formed on the side of a hot surface it cannot disengage itself as rajiidly as 
from the top of a horizontal surface. In the second place, there is less 
contact of the heated gases with the sides of the vertical tubes than with 
the sides of the horizontal tubes. 

By making the tubes of vertical fire tube boilers very long and liy 
giving a very high proportion of heating surface to grate surface, their 
duty may be improved. This type is best adapted for road engines, 
launches and steam fire engines. The sphere would be the strongest shape 
if it were possible to employ it. It lias also the advantage of not being 
distorted by expansion, but it would entail too much loss of space if used 
for shells, and it has less heating surface for its volume than any other 
surface that can be suggested. Boiler ends and steam drum tops are often 
made spherical. 

Next to the sphere the cylinder is the strongest form, and it certainly is 
much more convenient in construction than the sphere. By its use stays 
and braces are not needed. Sometimes it is necessary to have flat surfaces 



122 BOILERS. 

in boiler making, by reason of the necessity of economizing space and the 
proper arrangement of the interior parts of the boiler. In cylindrical boilers 
we find flat heads and tube sheets. 

Laterally Fired Horizontal Cylinder Boilers.— The simplest 
type is a plain cylinder set in brick work. It is easily cleaned of scale, is 
very strong, easily examined and repaired, is cheap, steams well, and primes 
little. The plates over the fire are, however, apt to become overheated. 
They should be suspended in the furnace from two points in their length, 
each one-fourth from the end, being held by wrought-iron bolts from pieces 
of T iron riveted on the the upper part of the shell. 

Internally Fired Boilers.— Those in use in America are generally 
vertical, flue or tubular, or locomotive type. The Cornish boiler is a 
horizontal cylinder with flat ends and one large flue passing from front to 
back and riveted to the two ends. In this flue is the grate. The products 
of combustion pass through the flue to the back ; return through brick flues 
along the side to near the front end, and then along the bottom to near the 
rear end; whence to the chimney. The course of the gases being from 
above downward is an advantageous one ; there are good circulation, large 
water surface, and hence little priming and no waste steam. The Cornish 
boiler evaporates about eight pounds of water per pound of coal, burning 
about ten pounds of coal j^er square foot of grate per hour as a maximum. 
It is well to have the internal flue corrugated, as allowing it to expand in 
length before the external shell is heated. The Lancashire boiler has two 
internal flues instead of one, thus lessening danger from collapsing. The 
Fairbairn boiler is a modification of the Lancashire, and is really an 
internally fired elephant boiler. There are three cylihdrical shells — two 
below, containing one flue each, and one above. The Galloway boiler is a 
modification of the Lancashire. The two furnaces at the front end unite in 
one flue of an irregular oval form. In this flue are conical upright water 
tubes which not only support the flue but break up the flame and cause rapid 
water circulation and uniformity of temperature, avoiding unequal expansion 
and contraction. The duty of this boiler is about eight and fifty-one- 
hundredths (8.51) pounds of water evaporated, per hour, per pound of 
anthracite and nine and eighteen-hundredths (9.18) pounds, per hour, per ' 
pound of bituminous coal — each square foot of grate consuming eight 
and eighty-seven-hundredths (8.87) pounds of anthracite or seven and 
twenty-seven-hundredths (7.27) pounds of bituminous coal per hour. 
The " two-story " or Righter type of boiler is particularly affected in 
Philadelphia ; and if that city had never known it, there would be fewer 
widows and orphans there. It is especially subject to violent oscillation of 
water in the gauge. 

Tubular Boilers. — In the tubular boilers the heated gases pass 
through tubes of comparatively small diameter, which pass through from one 
head to the other, under the water line, and are expanded into the heads. 
The type is a good one, if not exaggerated by making the tubes too long and 
of too small diameter. It is to be recommended where there is no liability 
to form scale. Too many tubes, or a proper number placed too close 



INTERN ALL V FIRED BOILERS. ETC. 123 

together, may impede circulation, and thus lessen instead of increasing the 
evaporation, and may cause priming and over heating of the plates just over 
the grates. The combined area of the tubes may range from one-seventh to 
one-twelfth that of the grates — the first being for severest firing of stationary 
boilers with chimney draft (or for forced firing, if the consumption of coal 
per square foot of grate per hour be less than twenty pounds per hour), and 
the latter for the same boiler with fifteen pounds of coal burned per square 
foot of grate per hour. The slower the combustion the shorter the tubes 
must be. The longest tubes kept in stock by dealers are twenty feet ; but 
even that is seldom called for, as the greatest length common in tubes under 
four inches diameter is sixteen feet. With tubes five to six inches in 
diameter they may be made twenty feet long with little fear of lessening the 
draft or water circulation. Three-inch or four-inch tubes are better only 
twelve to fourteen feet long than sixteen, although sixteen-feet tubes may be 
used with forced draft. But even in this last case it is better to have a 
damper in the chimney to increase the pressure of the gases in the tubes, and 
thus by retarding their flow give them more time to yield up their heat to the 
water in the boiler. 

It is best to range the- tubes in rows, so that they do not become 
fouled by scale as when set " staggering." Three-inch tubes are the 
most common size. The clear space between the outer side of the 
tubes should be about one-third their tube diameter, and the top of the 
upper row may be two-fifths of the boiler diameter from the boiler top. It 
may be necessary to make the top of the upper row come a very little above 
the two-fifths line in order to prevent the bottom of the lower tubes from 
coming too close to the bottom of the boiler. When there is liability to 
scale formation, the tubes must be a little further apart than one-third their 
diameter. The heads in which the tubes are expanded should be large 
enough to withstand the great pressure which tends to bulge them. The 
tendency to deform these flat sheets is greater than that operating on the 
convex part of the shell. In this last portion there is, if it be truly 
cylindrical, no tendency to deform. In fact, if it was not perfectly 
cylindrical in outline the outward pressure would tend to make it true. The 
heads should range in thickness from three-eighths of an inch in boilers 
thirty-six inches in diameter to five-eighths of an inch in boilers sixty inches 
in diameter. 

For very high pressure and shells of very great diameter it is better to 
make them of steel than of extra thickness of iron. In counting up the 
heating surface of a tubular boiler add two-thirds the surface of the shell 
to the entire exterior surface of the tubes. 

Sherwood's experiments go to show that there should be twenty- 
five times as much heating surface as grate surface, and eight times 
as much grate surface as tube area. These experiments were on 
marine boilers. The ordinary stationary boilers generally have the heat- 
ing surface to the grate as thirty to one, and the grate to the tube area 
as eight to one. , 

9 



124 



BOILERS. 



A compound tubular boiler now in mind has the following dimensions: 

feet. 



Length of boiler, 
Diameter of main shell, 
Diameter of drum, 
Number of 3-inch tubes, 
Size of grate, 
Height of chimney. 
Cross area of chimney flues, 



COLLECTIVE QUANTITIES. 



Water-heating to grate surface. 
Steam-heating to grate surface, 
Grate surface to tube area. 
Grate surface to chimney area, 



15 
5 

34 inches. 
140 

5x6 feet. 
100 " 

1 1. 1 square feet. 



65 to I. 
3-3 to I. 
5.2 to I. 
8.1 to I. 



A boiler of this proportion and size supplies a double cylinder non-con- 
densing 22 X 48 automatic cut-off engine of 325 indicated horse-powers, and 
furnishes steam for heating and drying. 

Tests of evaporation, using Cumberland coal on a three days' run, gave 
the following results: 



Duration, 

Fuel consumed, . 

Ashes, . 

Percentage of ash, 

Combustible, 

Water evaporated. 

Boiler pressure. 

Temperature, feed water. 

Temperature, escaping gases, 

Fuel per hour per square foot of grate. 

Water per hour per square foot of heating surface, 

Water per pound of fuel, under observed conditions 

Equivalent per pound of fuel from and at 212°, . 

Water per pound of combustible under observed condition 

Equivalent per pound of combustible from and at 212 



35.5 hours. 
34,938 pounds. 

2,365 

6.7 per cent. 
32,573 pounds. 

388,044 " . 
81.-7 

205 degrees. 

389 " 
10.94 pounds. 

1.87 
11.08 

11-55 
s, II. 91 

12.42 " 



The steam is said to have been perfectly dry. Evaporation is about 
11.000 pounds per hour. As the engine showed on a three hours' test con- 
sumption of 29.7 of steam per indicated horse-power per hour, the boilers 
must have been giving about 370 horse-powers. A common tubular boiler of 
the size of the main shell of this boiler would be rated at about seventy-five 
horse-powers, this one being rated at 125. These compound boilers thus 
give two-thirds more boiler power in a given floor space, and seventeen per 
cent, more steam for the fuel than the common cylindrical tubular boiler. 

Tubular boilers are generally used. They steam well, but are not to be 
recommended where the feed-water forms scale, because they are difficult to 
clean. If there are too many tubes they are apt to prime, and the plates 
just over the fire are likely to overheat. 

"Water Tube or "Tubulous" Boilers. — In these the tubes are 
of small size and without rivets; hence they are strong. They are cheap to 



BOILER PROPORTIONS. 125 

build and to keep in order, are easy of transportation, readily conform to 
different places, are susceptible of enlargement, and their economy is high. 
But by reason of their small amount of water room they are liable to fluctua- 
tions of pressure and to scale; they are apt to prime and to overheat. Their 
horizontal or inclined tubes do not allow the steam to escape well; hence 
their steam is generally wet. The steam gathering in the water tubes renders 
them liable to be burnt, this danger being the greatest with the highest duty. 
They are liable to deposits of sediment and scale upon the tubes, and if they 
do not scale they are almost sure to corrode. 

The French, or Elephant Boiler. — This is made of several small 
cylinder boilers and a shell, the shell being above as a steam drum. The 
necks of communication should be large and frequent. 

Boiler Proportions. — In proportioning boilers there are certain things 
to be taken into consideration which will not enable the best theoretical 
shape to be used. This is sometimes by reason of the best size not accord- 
ing with the commercial size of boiler plate. While a long grate is better 
than a short one to eft'ect complete combustion, there is a certain limit, gen- 
erally fixed at about seven feet, by reason of the desirability of having the 
boiler kept clean and the fuel evenly spread over it. If longer than seven 
feet it will be difficult, if not impossible, to keep the fires even on the 
back end. 

It is not best to have the grate surface wider than forty-two inches. In 
order to make the surface roomier, and to facilitate firing at the back, the 
grate slopes down from the front to the back about one inch to the foot. If 
the ash pit is too small, the air will rush through it too fast to supply the 
combustion on the grate. The incoming air should have as low a velocity 
as possible. The height of the surface above the grate must be sufficient to 
let the gases of combustion mingle properly. The higher the rate of com- 
bustion, the higher the furnace should be. In marine boilers twenty-four 
inches of height is enough, while in locomotive forty-eight is common. Bi- 
tuminous coal needs a larger combustion chamber than anthracite. The 
gross area of space over the bridge wall should be as small as possible, to 
give the gases a high rate of speed in passing this point. By this means they 
are allowed to mingle more freely. The higher the rate of combustion, the 
larger in proportion this cross area should be. The more rapid the draft the 
larger this cross area must be. It is best that the bridge wall opening 
should extend all of the way across the furnace, and that the cross area 
should be regulated by the height. 

The back smoke connection should be large in order to give the gases of 
combustion time and opportunity to complete their combinations before en- 
tering the tubes. There should also be room enough to admit a man for the 
purpose of making examinations, repairs, &c. Water spaces should be as 
wide as possible, and never less than four inches in the clear. There must be 
room enough between the furnace and the tubes to let a man in to scale the 
crown sheet of the furnace and to make repairs. For this purpose also there 
should be man-holes not smaller than 13 x n inches, and better, 15 x 12, oval 
in shape. The larger the water level the less trouble will there be with foam- 



12fi nOfLERS. 

ing and jiriming. If the steam spare is too small there will be trouble from 
the water lifting into the steam pipe when the engine makes sudden demands 
upon the boiler. 

Wherever boilers are intended to carry high pressure steam, the furnaces 
must be cylindrical, and they must be perfectly cylindrical, being made 
with butt joints and not with laps. The strap should be inside of the flue, 
on one side, and below the grate. If so placed, it will be accessible for 
calking, will not be in contact with the fire, nor in the way of hauling the 
ashes. The lengthwise seams would be better if welded instead of riveted. 
Long flues should be stiffened by flanges or by encircling bands at suitable 
lengths. In the Adamson joint, two outward flanges of the flues come 
together with a five-eighths inch wrought-iron ring between them, the sec- 
tions being connected by single riveting. By this method the fire does not 
touch any laps or rivets, and the joint may be calked both from the 
inside and the outside. Sometimes the different lengths of the furnace flues 
are connected and stiffened by T iron rings. When this is done, there should 
be an interspace left between the two ends of the flues. This allows the 
joint to be calked from the inside as well as from the outside, and there is 
also less liability to overheating at the seam. With such a joint as this, the 
two flue lengths must have exactly the same diameter, or the joint will give 
trouble. 

In long boilers there is often serious trouble by grooving, owing to the 
contraction and expansion of the furnace flue. To lessen this trouble, the 
" bowling hoop " is used. The disadvantage of the bowling hoop is that 
there is a double thickness of plate, and the rivet head.s are in the fire at 
each joint. An angle iron hoop is preferred by many to one of T iron. It 
is best made in halves, so that it may be passed in at the man-hole, and then 
riveted to the tubes in position. This obviates the removal of the tubes or 
cutting any holes in the boiler. It is best not to let the angle iron touch the 
tube, but to make the interior of the hoop two inches greater than the out- 
side diameter of the flue, placing rivets six inches apart and letting each 
rivet run through a blocking piece about an inch long. The angle iron 
hoop has the advantage over the T hoop that its single flange hinders the 
escape of steam less and gives less room for deposit. 

All smoke connections must be so designed and made as to give the 
gases large and free passage. As it is necessary to get at the tubes for 
sweeping, replacing or calking, the smoke connections are often provi- 
ded with large hinge doors. Sudden enlargements should be avoided; 
there should be no sudden bends; the current of gases coming from 
one set of flues should never cross other currents entering the same 
passage, and they should be partitioned apart until they both have the 
same direction. 

With high pressure cylinder boilers it is preferable to make the boiler 
proper complete in itself, making the front connections and uptake separate 
structures. It is necessary to line the uptake and connection with fire 
bricks. The uptake must be strong enough to carry its own weight and that 
of the smoke pipe. 



DRAFT AREA OF BOILER TUBES. 



127 



Draft Area of Boiler Tubes. — The appended table gives the draft 
area and heating surface of boiler tubes and flues, which have been computed 
on the basis of the thickness of such tubes taken from the price lists of 
American manufacturers. This table will be useful to designers and users 
of steam boilers, and save time in calculation in ordinary practice: 









Heating Surface 


Number of Tubes 


External 


Draft Area 


Draft Area 


per Foot in 


or Flues=i 


Diameter in 


in 


in 


Length, in Square 


Square Font of 
Draft Area. 


Inches. 


Square Inches. 


Square Feet. 


Feet. 


I 


■575 


.0040 


.2658 


250.0 


IK 


.968 


.0067 


.3272 


149.3 


I^ 


1.3S9 


.00964 


■3927 


103.7 


I^ 


1. 911 


-0133 


•4581 


75-2 


2 


2.573 


•0179 


•5236 


55-9 


2X 


3.333 


.0231 


.5891 


43-3 


^% 


4.083 


.0284 


• 6545 


35-2 


23^ 


5.027 


■0349 


.7200 


28.7 


3 


6.070 


.0422 


■7854 


23.7 


zVat 


7. 116 


.0494 


-8508 


20.2 


3% 


8-347 


.05S0 


.9163 


17.2 


3% 


9.676 


.0672 


.9816 


14.9 


4 


1093 - 


0759 


1.0472 


13.2 


4K 


1405 


.0976 


I.1781 


10.2 


5 


'7-35 


.1205 


1.3090 


8-3 


6 


25.25 


-1753 


1.5708 


5.7 


7 


34-94 


2426 


1.8326 


4.1 


8 


46.20 


-3208 


2.0944 


3-f 


9 


58.63 


.4072 


2.3562 


2.5 


lO 


72.23 


.5016 


2.61S0 


2.0 



In a flue return tubiilar boiler the area of flues should be about 20 per 
cent, and the draft area of uptake about 25 per cent, greater than the draft 
area of tubes. Good conditions for combustion and steaming are realized 
when the grate surface is 8 times and the heating surface about 200 to 240 
times the draft area of tubes. 

In the construction of steam boilers there are many other things to be 
done besides putting plenty of grate and fire surface. The fire surface must 
be properly disposed and located, and the circulation of the water must be 
good, so that the plates will not be burned on the fire side. The boiler 
should be as hot in one place as in another, to prevent injury from expansion. 
It should be readily accessible for cleaning and repairs. The water spaces 
should be ample. The stop valves must be readily got at, and such as to be 
opened or closed quickly and tightly. The velocity of steam in the pipes 
should not be more than 100 feet per second. 

Steam Room. — -A certain amount of steam room is necessary in order 
to prevent the lifting of the water in the boiler, when sudden demands are 
made upon it by high piston speed; but too much steam room makes the 
boiler too large and too heavy, and increases the cooling surface. The 
higher the rate of expansion and the fewer revolutions per minute of the 
engine, the more steam room is required. Marine boilers generall}' have 
about eight cubic feet of volume for each cubic foot of water evaporated per 
hour. Of this volume about one and five-tenths cubic feet are in the steam 



128 



no ILEUS. 



room, and six and five-tenths in the water room, furnaces and tubes. The 
steam room should, under the most favorable circumstances, contain at least 
enough steam to last the cylinders fourteen seconds; and it would be well to 
have enough to last the cylinders twenty seconds. A high and narrow steam 
room is better than the same volume with greater lateral dimensions. For 
this reason steam drums are of more use simply as steam room than steam 
space in the shell below them ; for this reason, also, steam chimneys, that is, 
annular steam spaces surrounding the base of the chimney, are very efficient, 
because they not only superheat by reason of the increased heating surface, 
but, by affording great height of steam room, permit the water that is carried 
up mechanically to be deposited and not carried over. 

Weakening Effect of Common Steam Domes. — AV. Barnet 
Le Van, a prominent engineer of Philadelphia, who has given much atten- 
tion to the causes of steam boiler explosions, gives his views at length in a 
paper which we herewith reproduce, on the weakening effects of domes as 




Fig. 56. 



usually applied; his positions and deductions are wholly tenable, and we 
agree with them practically" and theoretically. He says ; "The weakening 
effect of cutting large holes in boiler shells for receiving steam domes, or 
drums, is well known among boiler makers, and in order to preserve as 
much as possible of the original strength of the shell they cut a hole much 
smaller than the diameter of the steam dome, with the idea that the shell is 
weakened only in proportion to the size of the hole cut, which is a great 
error. The weakening effect is proportioned to the section of the dome 
adjoining the shell, independent of the size of the hole cut. The effect of 
an equal pressure upon both sides of that part of the shell covered by the 
dome is to deprive it of its direct acting tensile strength, in resisting an 
enlargement of the circle of the boiler, and to substitute in its stead that 
resistance made by a curved plate pulled in the direction of its chord. As 
this is but an inconsiderable fraction of tensile strength, the boiler is 
weakened in proportion. To make this good tlie boiler should be stayed 



WEAKENING EFFECT OF COMMON STEAM DOMES. 



139 



to compensate for the section of plate represented by the diameter of the 
dome. But better still is to have no dome at all. If domes are used at all, 
great attention must be given to the construction of them. They should be 
contracted at the lower part, and connected to the shell of the boiler by a 
neck of moderate diameter, and of such strength as to thoroughly make up 
for the cutting away of the shell of the boiler. A simple calculation will 
show that, by increasing the dimensions of a 48-inch diameter boiler, 12 feet 
long, to 51 inches diameter, as much additional capacity will be obtained as 
is contained in two steam domes of the ordinary size (30 x 24), and the larger- 
sized boiler, without the steam dome, will resist more steam pressure per 
square inch than the smaller boiler with the steam dome attached. By 
slightly increasing the diameter of the boiler it is scarcely weakened, and the 
extra iron required will be but one-fifth that used in making the steam 




Fig. 57. 



dome, saying nothing of workmanship. A substitute for a dome is a pipe 
placed inside of the boiler near the top of the steam space, the upper part of 
the pipe being perforated with small holes. The smallest holes should be 
made where the ebullition is the greatest, which is over the fire-grate. It 
would require 250 holes of \ inch diameter, or 1,000 holes of \ inch diam- 
eter, to give the area of a circular opening of 4 inches diameter. (Fig. 56.) 
It is not generally known, but nevertheless is a fact, that a large number of 
boilers sent out are under internal strains, resulting from bad work- 
manship, which, no doubt, in some cases will equal the proposed working 
pressure. These strains reduce the ultimate strength of the boilers 



130 BOILERS. 

independent of their being further weakened by cutting large holes for 
domes or necks. 

" The pressure in a cylinder boiler practically radiates from the axis of 
the cylinder to the circumference, tending to preserve the circular form, 
and tlius keep the plates of the shell in equal tension. Now, when a steam 
dome is used with a small hole cut in the shell this effect is destroyed, from 
the fact that, the instant the pressure inside and outside that portion of the 
shell plate covered by the dome are equal, it becomes merely a bent stay 
and affords but little strength to resist the bursting pressure on the shell of 
the boiler, having a tendency to become straight, as shown by the dotted 
lines at A (Fig. 57), and having no support from internal pressure to assist it 
in keeping a cylindrical shape, the pressure under and over the shell being 
the same as shown in the cut at X, causing the shell of the steam dome to be 
thoroughly strained and brought to a bearing, thereby stretching the boiler 
shell plates to the extent of their greatest elastic limit, and reducing its 
strength to a minimum." 

Boiler Flues and Tubes. — One method of fastening the tubes 
into the tube sheets is to expand them by means of special tools, which 
not only give the metal perfect contact with the sides of the holes in the tube 
sheets, but in some cases form shoulders either inside or outside, or both. 
Another method is to drive m a ferrule, which may be riveted over the end 
of the tube. Ferrules, while they make a tight point, obstruct the draft, 
and not only prevent the cleaning of the tubes, but give lodgment for soot 
and ashes. Tube ends should be annealed before being expanded. If 
the point is properly made the tube is not only perfectly tight, but acts as 
a stay or brace between the two sheets ; but the tube plates must have 
some play to allow them to give when the tubes expand, or else the tubes 
must have a chance to bend sidewise, which will be the case if they are 
very long. The tube plates should be good and thick, so as to give enough 
bearing to make a good point and to be stiff. The holes must be just the 
diameter of the tubes, so that the tubes need not be expanded excessively, 
which is apt to split them. It is better to counter-bore at the outer side, 
and to take off the burr on the edge of the sheet. The tube is cut about 
one-half inch longer than -the extreme outer distance between the sheet 
faces, one-fourth inch being left at each end to project ; this one-fourth 
inch is expanded, sometimes slightly turned over. Boring the tube holes 
slightly conical with the large diameter outside gives the tube greater holding 
power. In some boilers the sheet is made very thick and, instead of being 
bored conical, there is a shoulder or counter sink from the outer 
side, allowing the tube ends to be turned over in the ledge. This 
arrangement saves the tube ends from wear by the action of solid articles 
which are borne through them /at so rapid a rate. The ends of small tubes 
may be riveted over, after expanding, by a " boot-leg " tool or, if the tube is 
large, by means of a round-faced copper hammer. Steady rolling the tube 
ends over with the expanding tool is much better than with the quick blows 
of the hammer. There is such a thing as too much expansion of tube ends ; 
they may be made too thin by this process. If the pressure will be from 



BOILER FLUES AND TUBES. 131 

within, forcing the heads out, it is better to expand the tubes on the outside 
ends; but if the pressure tends to push the tube sheets together, the shoulder 
should be on the inside. In taking out expanded tubes, iron ones are gen- 
erally rendered of no value, and brass ones must have new ends and brazed 
on. Copper will not do for tubes of locomotive boilers, because the friction 
of the cinders, caused by the artificial draft, wears it out. It will not do for 
marine boilers, because of the galvanic action between copper and iron in 
the presence of salt water. There is some trouble also in using copper tubes 
with iron boilers, by reason of the different expansion of copper and iron by 
heat. Brass tubes have all of the advantages of copper, and none of their 
disadvantages. They are ductile, have greater conductivity than iron, ex- 
pand less under heat than copper, do not corrode, and do not produce much 
galvanic action. They are more expensive in first cost than iron tubes, but 
are more injured by burning than iron. Brass tubes are less injured by ex- 
panding them in the tube sheets than iron. 

Corrosion will render the tubes unsafe sooner than the plates, because the 
tubes are thinner than the plates, and though, because of their smaller di- 
ameter and the pressure being on the outside, the tubes will bear just as 
much pressure as the shell, when both are of their ordinary thickness, a 
diminution of one-sixteenth of an inch in thickness might not render the 
plates unsafe, while the tubes would be so. 

Whitehead, an English engineer, has invented seamless boilers, each made 
from a single ring of cast steel, rolled to the proper dimensions for the cylin- 
drical shell, the heads being put on with bolts. There is no doubt that such 
a boiler must be stronger than one with lengthwise seams. 

Grate Bars. — It is important that the grate of a boiler shall have 
proper dimensions, construction and position, in order to give regular and 
thorough combustion of fuel, high duty, regular steaming, and prolong the 
life of the boiler, while lasting well itself and giving little trouble to the fire- 
man in handling various classes of fuel — of course, within a certain range. 
As regards the quantity of grate surface, Watts' rule was one square foot per 
horse-power, or per cubic foot of water evaporated per hour. But the grate 
required depends on the kind of water and fuel, the details of boiler and 
setting, and whether the draft be natural or forced. Watts' allowance may 
be reduced to three-fourths of a square foot for good, and one-half square 
foot for best coal. The square feet requisite for the various types of boilers 
may be found by dividing the number of pounds of water to be evaporated 
per hour (from and at 212°) by the following numbers: 

Cylinder 75 Vertical tubular 79 

Flue 77 Locomotive and portable 80 

Horizontal tubular 78 / 

Stationary boilers will l)urn, per hour, per square foot of grate, almost as 
follows: 

Natural Draft. Forced Draft. 

Bituminous 10 to 25 lbs. 20 to 50 lbs. 

Semi-anthracite 10 to 20 lbs. 20 to 40 lbs. 

Hard anthracite 8 to 16 lbs. 16 to 32 lbs. 



132 



BOILERS. 



Forced drafts necessitate thicker fires and greater care in firing than 
natural. The area per pound of coal for different types of boilers and differ- 
ent drafts is about as follows: 

For externally fired boilers, with moderate draft 08 sq. ft. per lb. of coal. 

" " with quick draft 06 

" " with forced draft 04. 

For internally fired boilers, with quick draft 03 

" " with forced draft 02 

For locomotive boilers 01 

It is best to make the grate surface somewhat excessive, so as to allow 
for poor coal and slow draft, and to reduce it sufficiently by brick work along 
each side wall. The annexed table, from Barr, shows the width and length 
of grates and the area in square feet, as usually supplied tubular and flue 
boilers; also the amount of coal required per hour when burned at the rate of 
12, 14, 16, 18, 20 pounds per square foot of grate per hour. 



Grate. 


Coal Required per Hour. 


Diameter 


















of Boiler. 


Width. 


Length. 


Area. 


12 Lbs. 


14 Lbs. 


16 Lbs. 


18 Lbs. 


20 Lbs. 


Inches. 


Inches. 


Inches. 


Sq. Feet. 


Pounds. 


Pounds. 


Pounds. 


Pounds. 


Pounds. 


36 


45 


48 


16.0 


180 


210 


240 


270 


300 


38 


47 


48 


15-7 


1S8 


220 


251 


283 


314 


40 


49 


48 


16.3 


196 


228 


26r 


293 


326 


42 


51 


52 


18.4 


221 


258 


294 


33 f 


368 


44 


53 


52 


I9.I 


229 


267 


306 


344 


382 


46 


55 


52 


19.9 


239 


279 


318 


358 


398 


48 


57 


52 


20.6 


247 


288 


329 


. 371 


412 


50 


59 


60 


24.6 


295 


344 


394 


443 


492 


52 


61 


60 


25.4 


305 


356 


406 


457 


508 


54 


63 


60 


26.3 


316 


368 


421 


473 


526 


56 


65 


72 


32.5 


390 


455 


520 


585 


650 


58 


67 1 72 


33,5 


402 


469 


536 


603 


670 


60 


69 ; 72 


34 5 


414 


483 


552 


621 


690 



In vertical tubular boilers there is not the same room for variation in 
grate area to suit the fuel as in horizontal; but the fuel must be chosen to 
suit the grate. Anthracite nut coal or crushed coke is generally best. Bi- 
tuminous needs slow burning and stoking in small pieces. To facilitate 
firing, the grate is usually set somewhat lower at the rear end. The mean 
distance with external firing should be about 30 inches when bituminous coal 
is used, 20 to 24 for semi-bituminous, and 18 for hard anthracite. The bars 
should get their strength from depth rather than width; and the problem in 
making them is to get as much air space as possible without letting the fuel 
through, and at the same time to render as light as possible the arduous labor 
of slicing. 

For burning saw dust, excellent results are obtained by using grate bars, 
made for ordinary furnaces, of flat plates of a width of about six inches, and 
running lengthwise of the furnace. Each of these plates has two ribs of a 
depth of about four inches by one-half inch thick, for supporting and 
preventing the plates from warping. The plates are perforated by holes 



GRATE BARS. 133 

three-eighths to seven-sixteenths of an inch in diameter, which are largest 
at the bottom to facilitate molding and prevent the holes from stopping up. 
(This style of grate has also been used for years upon locomotives for 
burning soft coal, and is adapted to burning coal dust, coke, and other 
miscellaneous fuels.) 

Coal is burned upon grates composed of alternate bars and spaces. 
In some cases there is a dead plate about twenty inches long without any 
perforations. This is at the front part of the grate, and is used with bitu- 
minous coal. Upon this grate the coal is thrown and partly volatilized by 
the glowing mass in front of it, the resulting coke being pushed forward 
when new coal is added. Overheating of grate bars is prevented, or partly 
prevented by the currents of air passing up beeween the bars, and also by a 
thin layer of ashes. The advantage of large air spaces is not only that they 
furnish a large air supply to support combustion, but they keep the grate 
bars cool. If bars are of a bad shape, or if the spaces are choked, or if 
the fire is too hot, the bars will bend vertically or warp sideways, and partly 
melt on top. Grate bars are destroyed more rapidly by "brassy" coals 
(those containing sulphur), or by those forming easily fused clinker, because 
the clinker chokes up the air passages and the sulphur rapidly eats into the 
hot iron. The top of a grate, should be accurately plane ; if any bar pro- 
jects above the level of the others, it is apt to be burned and to be displaced 
in stoking. Hollow grate bars, through which a current of cold air or water 
passes, have been proposed and used; but they are expensive and difficult to 
keep in order; hence have not found their way into public favor and 
extended use. Wrought iron grate bars bend and warp more easily than 
cast iron, but they can be straightened again, which is not the case with cast 
iron. They are not so easily broken, melted nor fused as cast iron. They 
may be made thinner than cast-iron bars; hence will give more air space per 
square foot of grate surface, and are somewhat lighter than the cast iron. 
The easiest way of making them is to rivet two plain bars together with 
thimbles between them for distance pieces at the ends and in the middle, the 
heads of the rivets being half as high as the desired space between the bars, 
so that if all the rivets are in line the bars will be of an even distance apart. 
Short bars are easier handled than long ones, and are less apt to warp or 
twist by overheating. Grate bars should be thicker at the top than at the 
bottom to facilitate the inflow of air, the fall of ashes and the slicing 
of the fire from below. If the bars are over thirty inches long, they 
should have projections at the middle of their sides to stiffen them. They 
are generally made in pairs so as to give less trouble in handling, and 
the single bars are provided in order just to fill the grate width if an odd 
number of bars is needed. In order to prevent clinkers from sticking to 
the bars and filling the air spaces, it is well to have a shallow groove in the 
top edge of the bar. This will not only prevent the clinkers from sticking, 
by reason of the ashes it will contain, but will, for the same reason, slightly 
prevent melting or burning of the top of the bar. There should be allowed 
at the end of tne bar a space not less than the width of the air space, in 
order to allow for the expansion of the bar. 



134 BOILERS. 

Boiler Setting. — Not only the economy of fuel consumption and 
the regularity of steam generation, but the life and safety of the boiler very 
largely depend on the mode of setting. As a rule, boilers are bought of 
makers more or less conversant with proper proportions in construction, and 
set by other parties than their builders — by parties who are not informed 
concerning the proper relations of grate and heating surface to length, 
cross section and position of flue passages, and who are not interested in 
producing from the boilers they are given to set any special amount of steam 
per pound of coal or per square foot of grate or heating surface. It is per- 
haps within the bounds of accuracy to say that four out of five boilers are 
badly set. The mode of setting boilers should be determined principally 
by the nature of the boiler and of the fuel ; and the style of boiler should be 
carefully decided upon by the nature of the service desired. It must be 
remembered that perfect combustion is the first and principal desideratum. 
Without this no good results can be obtained or expected ; with it many 
minor disadvantages are in part counteracted. 

Horizontal, Externally Fired Cylinder Boilers. — A very 
common and cheap mode of setting horizontal, externally fired cylinder 
boilers employs straight walls only at the end, the back end having a hori- 
zontal cast-iron plate or bracket riveted to it, by which it is upheld by the 
rear wall of the brick setting. This plate arrangement is better than arching 
over the rear end, as in the case of tubular boilers the rear ends of the tubes 
are quickly and readily accessible and seen under good lights for examina- 
tion or repairs. Still the arch offers the best passage for the gases of 
combustion. Bricks are better than stone for foundations. Brick walls are 
much better hollow (that is, of two single thickness.es with an air space 
between them) than solid. The walls are carried up straight to the level of 
the top of the shell, and filled in with some good non-conducting material, 
either solid or filled with air spaces, the latter being far preferable. A mixt- 
ure of sawdust, coal ashes (not wood) and plaster of Paris, makes a good 
insulator. It should not touch the iron boiler shell, but be separated from it 
by a wooden lagging, made by kerfing out strips an inch thick, four inches 
wide, and long enough to reach over and around the upper semi-circum- 
ference of the shell, and building up the arch (by narrow board strips) laid 
on these arches, which latter are about three or four feet apart, and hold the 
boards off from the shell and leave an air space. It would, perhaps, be 
about as well to cut these longitudinal strips into lengths equal to the dis- 
tance between centres of the arched bearers, so that sections of three or 
four feet in length of the board lagging may be removed at will. Every 
precaution which facilitates ready examination is valuable and desirable. 
To carry out this idea more completely, the writer has devised a mode of 
making the non-conducting covering or plaster, in readily removable sections. 
This is to lay on top of the board lagging, before " grouting " with the 
plaster, some lengths of wire which hug the lagging closely, their ends com- 
ing up at the sides, so that when the plaster begins to set, these wires may 
be used to cut it into blocks, any one of which may be removed without 
disturbing the others. All the iengtliwise wires ma)' be hiid down first, and 



HORIZONTAL CYLINDER BOILERS. 135 

then all the cross wires ; they being removed in the reverse order. Sand 

should never be used, either wholly or in part, for this filling. It is best to 

cover the top of it with a stout canvas, which will prevent the percolation 

of water through the joints and consequent rusting of the outer surface of 

the plates. Where a brick arch is used, it should not be allowed to touch 

the boiler shell, especially if the joints be made with lime mortar. But the 

use of lime mortar in boiler setting cannot be too strongly condemned. In 

the furnace proper, fire clay should be used to make the joints of the fire 

brick there necessary. Some shells are upheld by cast-iron lugs riveted to 

the shell at its medium line. They should correspond accurately to the 

curve of the shell, and be of suitable braced shape in order that they may 

not crack or give way. In a 12-foot boiler four are necessary, two on each 

side, they should be placed three feet from each end. Sometimes, to allow 

for expansion and contraction in length, the rear end is left to be supported 

on rollers, instead of being hung by the lugs. The same object would be 

attained by setting a plate in the brick work under each rear lug and putting 

a roller between it and the lug. The plate should extend a little further 

back than the lug, and there should be a brick abutment at each end to 

keep the roller in place. ". crop end of 2^-inch shafting would make an 

excellent roller. It must be remembered that the expansion and contraction 

of a boiler, unless allowed for (no earthly arrangement will prevent it), will 

surely break up and destroy any setting. When a mud-drum is used (and 

it is generally desirable to have one, say one-third the diameter of the boiler 

shell, and fitted with a man-hole as well as with blow-offs), it may extend 

either across the under side of the boiler, forming a support for the rear 

end, or it may run lengthwise and its head project through the rear wall. 

The walls heretofore referred to are for supporting the shell. There are 

others built across to form furnace and ash pit. The first from the front end 

is the bridge wall, which is peculiarly subject to destruction by the fierce 

heat playing around it. It should be of special thickness (preferably hollow), 

and faced with fire bricks. The fire-brick furnace walls should be brought 

up to the water line. The grates have a rest of about an inch in the bridge 

wall plate, and on a bearing bar fastened in the fire brick. They are 

generally slightly the lowest at the rear end, to facilitate stoking. As 

regards distance from the under side of the boiler, it should be regulated 

strictly by the kind of fuel. Many a time a new lot of good coal has been 

unjustly condemned as poor for steaming purposes, when it was simply un- 

adapted for the grate, or the fire-box too high or too low — generally too high. 

For hard anthracite, 18 inches are sufficient fire-box height, 24 inches for 

semi-bituminous, and 30 inches for bituminous coal proper. In a 12-foot 

boiler, 48 inches in diameter, good usage sanctions the following dimensions 

and distances : 

Inches. 
Height of centre line from ground 80 



Height of lower end of grate from ground, . 

Length of grate, net, ....... 

Distance from top of grate to bottom of boiler, . 
Thickness of bridge wall and mud-drum wall (if solid), 
From centre of bridge wall to centre of mud-drum wall, 



vanes 

55 

varies 

18 

64 



136 



BOILERS. 




SMOKE CONSUMERS. 137 

Inches. 

Thickness of back cross wall \ .^P' ' ' 3 

( bottom, ...... 19 

Distance of centre of rear wall from centre of back cross wall, . . 29 

Thickness of rear wall, ......... 13 

Height of rear cross wall, . . ... . , . . . 51 

Height of mud-drum wall, ........ varies 

Height of bridge wall, 44 

Depth foundation walls below ground level, ..... 30 

Thickness of side walls, if solid, ........ 13 

Side walls, out to out, 83 

Side walls, in to in, . . . . . . . . . . 57 

The boiler should be slightly inclined (say one inch in ten feet) toward 
the blow-off pipe at the back end, and this should be so placed as to drain 




Fig. 59. — Boiler Front, with Smoke Consumer. 

the boiler dry if needed. Long boilers should not be hung from three 
points; for, as they are heated more at the bottom than at the top, they will 
be expanded more on the bottom than on the top, and the ends will be thrown 
up, thus putting most of the weight upon the middle support. 

Furnace Doors. — It is a good idea to have a swinging door just 
underneath the main furnace door, of which it may form a part. This will 
enable the fires to be sliced, without checking the steam capacity by 
opening the main door. Besides this, it shields the fireman from the 
intense heat of the fires. 

Smoke Consumers. — Fig. 58 shows the McGinniss smoke consumer 
in section, and Fig. 59 the same in front view. This smoke consumer has 
an adjustable door, which can be raised or lowered by a lever, in front of the 



138 BOILERS. 

boiler, and held in jjosition by a pawl and ratchet, this door being to regulate 
the air supply. After firing up, it is set to suit the rate of combustion, and 
should require no further attention. This is the proper i)lace to regulate 
the air supply, being better than back dampers. The door also deflects the 
air supply directly upon the flames. There are deflecting arches of terra 
cotta or other non-conducting material placed at intervals beneath the boiler, 
and serving to deflect the cold draft from the under surface of the boiler. 
The back wall of the furnace is hollow, and air is admitted through it from 
the ash pit and, entering behind the fire, improves the combustion. The 
current of gases of combustion from the grate passes under the first arch 
and through the second, which last is hollow, and through which enters a 
stream of fresh air which, by virtue of the action of the drop arch, be- 
comes a counter current, and oxidizes the smoke in the gases of com- 
bustion. The proper dimension and position of this second arch are 
matters to be carefully determined. A member of a firm making such a 
device states that he has effected a saving of 21 per cent, of the fuel, and 
the manufacturer says that he is willing to warrant from 10 to 20 per 
cent., according to the circumstances, although in every case he guar- 
antees 10 per cent, over the old system of plain furnace. The number or 
arches is proportioned to the length of the boiler, always with the same end 
in view— the deflection of the currents from the boiler surface. The price 
of this extra setting is about $150 per boiler. 

Chimneys. — The chimney should have an area of about one-eighth 
that of the grate. If of wrought iron, it should be about twenty-five dia- 
meters high, and provided one-third of its length from the top with a 
wrought-iron band, to which are to be secured three guy rods; these are best 
made of wrought-iron rods linked together with welded rings or eyes; the 
diameters will vary from five sixteenths to one-half inch, depending upon 
the height and weight of the stack. 

Co"wls. — There are cases where the prevailing winds interfere with the 
draft of the chimney, and demand some appliances to accommodate the 
draft. For this purpose a cowl is generally used. It is so arranged that the 
opening for the escape of the smoke, which would otherwise blow down 
the chimney, is blown away from the direction of the wind. Cowls are 
used most where there is no one prevailing wind to contend with in this 
respect. 

Stearo. Pipe. — Steam must be taken from the highest part of the boilers, 
because there it is driest. In large square boilers the dry pipe has several 
side branches. The best means of making the holes is by saw cuts. The 
large end must be plugged up. Sheet brass is the best material, as there is 
special liability to corrosion. Where dry pipes cannot be used by reason of 
making the inside of the boiler inaccessible, deflecting plates may be used. 
A small stop valve is apt to cause foaming. To remedy this it is better to 
add another stop valve at the other end of the boiler than to enlarge 
the existing one, because the new valve will draw steam from another point, 
and tend to equalize the pressure. The steam pipe should have expansion 
joints between all rigid fastenings. If there are no straight lengths which 



STEAM PIPE— SAFETY VALVES, 139 

can spring in case of expansion, the check valve should have as little lift as 
possible. With a high lift there is hammering and consequent destruction 
of the valve and seat, followed by leakage. One-half an inch should be the 
maximum check valve lift. The area should be enough to keep the velocity 
of the water under 600 feet per minute. To insure seating of the check in 
large valves, the upper valve spindle is carried through a stuffing box, and 
bears a weight which causes prompt seating. For small stop valves, be- 
tween the check valves and the boiler, a plug cock is better than a globe 
valve, because it is less readily prevented from closing by solid matter getting 
in it. 

The dry pipe, having numerous small perforations on its upper side, is 
inserted in the upper part of the steam space of the boiler. This pipe does 
not dry the steam, but acts mechanically by separating the steam and water 
when the latter is in a violent state of agitation and is liable to be carried in 
bulk toward or into the steam pipe. The object of these numerous small 
holes in the pipe is that a small quantity of steam may be taken from a large 
number of openings at one time, and thus carried over a larger extent of 
surface than that afforded by a single opening, this simple device checking 
the tendency to prime. This pipe, leading from the boiler, is sometimes 
carried through the combustion chamber under the boiler, and thence to the 
engine ; a practice not recommended under any ordinary circumstances. 

Safety Valves. — The safety valve should be large enough to discharge 
at a given pressure, all the steam the boiler can make. It must close quickly 
when the pressure falls, by reason of its discharge below that point at which 
the valve is set to open. Each boiler should have its own safety valve, and 
each should be raised daily to prevent sticking. Both the valve and seat 
should be of gun metal to prevent rusting and sticking. The valve should be 
on top of the boiler, if possible ; if not, it should be connected with the 
highest part of the steam space. Every separate superheating chamber and 
feed- water heater should have a separate safety valve. The lever, where there 
is one, should be cut off at the point of maximum pressure, so that it will 
be impossible to move the weight farther out than allowable. Lock-up valves 
should be raised just the same as any other, else they are liable to be stuck 
fast. . The best way is to have a cord running from the lever over pulleys so 
that the valve can be lifted from the front of the boiler. One trouble of the 
ordinary safety valve is that it has a limited action and its lift decreases with 
adjustment for high pressures. With a diameter of six inches it gives an area 
of less than one square inch. This necessitates large diameters with the 
accompanying large friction surfaces and corrosion. 

Weighting may be accomplished either by applying the weight directly or 
by means of a lever. Coil springs are now very largely used for this purpose, 
and almost universally where the valve is directly weighted. Valve seats 
may be conical or flat. It is claimed for flat-seated valves, or disc valves, 
that they afford greater lift, are the simplest in construction, most reliable in 
action and the least liable to get out of order. A safety valve should be 
allowed to open occasionally, and not be excessively overloaded, and at least 
once each day, when in use, the valve should be opened by hand in order to 

10 



140 



BOILERS. 



insure its perfect action. Valves which embody these advantages in an emi- 
nent degree are the Scovell Pop Safety Valves, illustrated herewith (Fig. 60). 
Simplicity is one of their chief merits. Although these valves differ materially 
in principle, they give very similar results under ordinary working pressures. 
The one which we first describe is more particularly calculated for stationary 
and marine boilers. 




Fig. 60. — Scovell Pop Safety Valve. 



The following is a description and mode of operation of this valve . The 
passage E forms the steamway between the valves A and B. The passage F 
conveys steam from the boiler to the valve B. The passage D conveys steam 
from the boiler to the main valve A. The set screw L is for the purpose of 
regulating the lift of the main valve A. The cap surrounding the spring 
spindle M regulates the tension of the coil spring. The lever H is for the 
purpose of opening the valves by hand. The openings I I are for the pur- 
pose of allowing steam to escape into the atmosphere from the valve B. The 



SAFETY VALVES. 141 

elbow pipe C is for the purpose of allowing the steam to escape into the 
atmosphere from the valve A. The lock and chain secures the valve against 
being tampered with. The main valve A and lower disc of valve B are fitted 
so loosely in their cases that steam passes freely around and above them, 
constituting a counter pressure above the main valve A. The valve B, 
it will be understood, simply operates the valve A. The main valve A re- 
lieves the boiler. Atmospheric pressure acts upon the interior of elbow pipe 
C. The main valve A and lower disc of valve B are fitted so loosely in their 
cases that steam freely passes around and above them, forming a steam coun- 
ter pressure or load above the main valve A, which holds it down on the top 
of elbow pipe C, which forms its seat. When the valves are at rest, their 
chambers are filled with steam at boiler pressure, and at all titnes the boiler 
pressure acts upon the lower disc of valve B and the annular space surround- 
ing the seat of main valve A, but not so above them, as will be observed 
from the following description. The above description refers to the valve at 
rest, but we will now describe its action in "blowing off." As soon as the 
boiler pressure becomes greater than the resistance of the coil spring, the 
valve B is forced upward from off its seat. As this occurs, the steam press- 
ure above the main valve A and lower disc of valve B begins to escape into 
the atmosphere through the seat of valve B and openings I I. The boiler 
pressure continues to increase slightly until the valve B has opened sufficiently 
to allow the steam load above the main valve A to escape through the passage 
E, and through the seat of valve B, and into the atmosphere more rapidly 
than it can get on top of and around the loosely fitted valves. The main 
valve A then opens to its full height, and relieves the boiler of its excessive 
pressure through the elbow pipe C, when the coil spring again forces the 
valve B back to its seat, causing the pressure to again accumulate in the 
chamber above the main valve A, and force it back to its seat on top of 
elbow pipe C. The trip lever H is so arranged that a downward pressure 
causes it to lift the spring and cause the valves to " blow off," but an upward 
movement of the lever will not exert any force on the valve to hold it down. 
The pressure can be easily changed at any time, by altering the tension of 
the coil spring with the cap screw. 

It is claimed that the Scovell system of duplex valves gives many features 
of excellence, for the following reasons : Two valves are employed, as being 
highly desirable in severe and continuous service ; Accuracy of operation 
does not depend upon any delicate adjustment ; The seats are of the simplest 
form, and can be reground by any ordinary workman without impairing the 
efficiency and accuracy of the valves' action. No pressure accumulates after 
the valves open, and they close with a slight reduction of pressure. 

The safety valve, of which every boiler ought really to have two, should 
have an area of at least i square inch for each 2 square feet of grate 
surface. Another rule, ascribed to Professor Thurston, is to multiply the 
pounds of coal burned per hour by 4 ; this product is to be divided by 
the steam pressure, to which a constant number 10 is added. 

Example : What would be the proper area for a safety valve for a boiler 
having a grate surface 5 feet square and burning 12 pounds of coal per hour 



142 BOILERS. 

per square foot of grate ; the steam pressure being 75 pounds per square 
inch ? 

5^5 = 25 square feet of grate. 25x12=300 lbs. of coal per hour. 
300 X 4= 1200. 

75+10 — 85 = steam pressure with 10 added, then 12004-85 = 14. 11 inches 
area or 4^ inches diameter. 

Fractures, blisters, internal corrosion, internal grooving, sediment, scale, 
deposit are in no way under the control of the safety valve. 

The safety valve is often overloaded to save steam. An explosion 
occurred in Mississippi, in 1871, by which four men were killed. The 
following account tells the whole story : " The day previous to the explosion 
the safety valve was leaking. Instead of grinding down the valve a piece of 
gum packing was placed under it. This blew out; a new piece was put 
under, and then a brace was placed between the valve lever and the roof of 
the building to hold it down and retain the packing. Having thus got things 
well in train for a first-class blow up, the engineer got up steam, running the 
pressure up to 105 pounds, 'the last time he looked at the gauge'. He 
thinks there were two gauges of water, but is not sure, as two men were 
pumping in water at the time of the catastrophe. That two men were 
required to work the pump shows that this was out of order. In short, there 
was no one about the establishment that seemed to know much about any- 
thing, more especially steam, and, as a consequence, destruction swiftly 
followed their silly tinkering." 

Fusible Plug. — The fusible plug is made of some alloy melting at a 
very low temperature, it is placed in a hole in the boiler usually a little above 
the danger level; when uncovered by water it is melted and the discharge of 
steam at once relieves the pressure and gives the alarm. 

Pressure Gauges. — These should be tested every three months by a 
mercury column, so that it may be known whether they are right or not. 
There are plenty of incorrect steam gauges ; sometimes the gauge was incor- 
rect to start with, sometimes it has been neglected or injured. Inspection 
shows gauges varying from 40 pounds below to 60 pounds above the real 
pressure. The former case, of course, is one of extreme danger, because the 
gauge may have shown ioq pounds only when there were 140 pounds on. 
The practice of placing a stop valve between the boiler and safety valve 
cannot be too severely censured. It is a dangerous trap, even in the hands 
of a competent man. 

Glass Water Gauge. — A glass water gauge should be on each boiler; 
its lower gland on a level with the lower gauge cock. Gauge glasses should 
be large, so as not to be easily clogged by pieces of loose scale or other im- 
purities in the water. An improved gauge glass has the back of the tube of 
white enamel, the front being transparent. This renders the water level more 
easily seen. When the boilers foam badly, the gauges do not easily indicate 
the height of solid water. 

Draft Regulator. — This apparatus has the advantage of saving fuel, 
increasing boiler capacity, preventing excessive smoke, and keeping steam 
even. In addition, it lengthens the life of the boiler. 



GAUGES— FEED PIPE, &<•€. 143 

Feed Pipe. — The feed pipe is commonly screwed into a hole tapped 
in the back boiler head. To allow for clogging, sediment and scale, it 
should have an area double that requisite to pass the quantity of water. 
When the water is hard it should be disconnected from time to time to see 
that it is not filling up with crusts. Make the feed pipe short, straight and 
above ground. 

Wliere to put the Feed Pump. — The question has been asked 
whether the feed pump ought to go between the heater and the boiler, or 
before the heater, so that the latter will heat its discharge. As the feed pump 
will not lift very hot water, the heater must be placed between the pump and 
the boiler in those cases where the feed is not heated by direct contact with 
the steam. A pump will force hot water as well as it will cold. If the 
feed-water is taken from a stream in which there are floating particles of 
wood, leaves, etc., a strainer should be used. A large sheet-metal box with 
perforated sides makes a good strainer. The openings ought not to greatly 
exceed an eighth of an inch in diameter, and should be several times the area 
of the suction pipe. The feed pump should be four times large enough to 
run the boiler ; and the speed should be proportionately reduced. Feed 
pumps sometimes give trouble by intermittent action, working well enough 
for a few days and then stopping wholly or from time to time. This happens 
very often because of bends in the pipe, in the upper portion of which air 
collects. 

No one yet seems to have been able to say why it is that when the pump 
fails to work, a hammer is generally taken to start it up. It requires only a 
very small leak in a pump or in its connections to overcome the vacuum and 
stop the pump from working. If pump valves have spindles as guides, these 
should fill the holes and the seats should be straight lines, not curves. Valves 
that do not fit are apt to cock on their sides and leak. All boilers should be 
fitted with a cock between the check and the boiler, so that the check can be 
examined. Valves fitted with wings are apt to bind in their seats and stick 
fast. All pumps should be as close as possible to the source of supply. The 
higher the speed the shorter the lift on the feed side may be. Bear in mind 
that water is not compressible, and do not attempt to force it against closed 
cocks or valves. 

The Hancock Inspirator consists of a double apparatus in one casting, in 
one serving as a lifter, which raises water and delivers it to the other half, 
which forces it to the boiler without adjustment being needed for varying 
steam pressure. There are certain conditions about almost any good jet 
apparatus for boiler feed which are possessed in a high degree by the inspir- 
ator. There are no valves or movable parts to break or get out of order. 
All of the steam used to force water is condensed in the water, not only add- 
ing to the volume of feed-water, but heating it, and thus saving fuel and doing 
away with the cost of a heater. There is no oil needed. The inspirator will 
lift water twenty-five feet, with forty-five pounds steam pressure, and deliver 
it into tanks or in the boilers. It will take water as hot as 140° on a lift of 
three or four feet or under a head, and on a lift of twenty-five feet it will 
take it at 100° to 110° F. The temperature at which it will deliver the v/ater 



144 



BOILERS. 



depends upon the steam pressure, the temperature of the water drafted and 
the quantity of steam used upon the forcer side. The higher the steam press- 
ure, the higher the water would draft, and the more steam left in on the 
forcer side, the higher will be the temperature at which it will deliver water. 
With fifty or sixty pounds steam pressure, and about one-quarter turn of the 
handle on the forcer side, the water will be delivered from i6o° to 190° F. 
The temperature of the water delivered may also be increased by giving 
more steam on the starting valve, or by throttling the water supply. The 




OVERFLOW 

Fig. 61. — Section of Hancock Inspirator. 



lifter side alone will lift water twenty-four feet, and deliver it twenty feet 
above the apparatus, with forty pounds of steam, heating the water at 20°. 
With the lifter and forcer together it may be said that the water can be forced 
two feet above the inspirator for every pound of steam pressure. 

In applying and running the inspirator, care should be taken that the 
suction is tight, so as to give a good vacuum ; that the steam comes direct 
from the boilers, and from that portion of the boiler where it will be dry 
steam. Taking steam for the inspirator from the steam pipe has the disad- 
vantage that the steam will not be so dry as if taken from the boiler direct ; 
and, further, that if this steam pipe supply an engine cylinder, the supply to 



INSPIRATOR— STEAM TRAP, ETC. 145 

the inspirator will be apt to be irregular. Where it is absolutely necessary 
to tap a steam pipe, it should be tapped upon the upper side so as to avoid 
drainage. An inspirator cannot be run with hot water. In starting, any 
water that may be in the steam pipe must be let run off at the overflow. 
Sometimes the suction gets full of hot water. In this case it will be neces- 
sary to cool the inspirator and suction with cold water, or, better yet, to let 
the steam on and off suddenly at the starting valve until all the hot water is 
disposed of. As the friction of a long draft increases the quantity of water 
drawn, it will be best to have the suction pipe two or three times greater in 
diameter than the connections. The capacity of the injector should be such 
that it will deliver water just as fast as the steam is called for, so that it will 
be running constantly. The cut shows the inspirator in section. It must 
be remembered that the inspirator effects a considerable economy of fuel 
over feeding cold water, and also where the water supply is hot and regular, 
as with the proper size inspirator, there is no injury to the boiler from con- 
traction and expansion of plates, as is the case where cold water is pumped 
in spasmodically. 

Steam Traps. — There are three kinds of steam traps. The expan- 
sion trap is of two kinds, one composed of metals expanding differently 
under heat (as brass and iron), the other depending on the expansion of 
a liquid. As condensed steam is cooler than live steam, it closes the most 
expansible of the two metals so as to open a passage for the water. If there 
is a liquid to be expanded, live steam cools the orifice, and condensed steam 
opens it. The functions of a good pot trap must be to discharge the water 
of condensation from coils or from the cylinder of an engine into a tank or 
sewer at a higher level than that which it drains, keeping the coils of the 
cylinder dry. To be of real economy, a trap should discharge the water of 
condensation back into the boiler. The pot trap is not economical by reason 
of its not discharging water down to atmospheric temperature and pressure 
under any condition of temperature of the water in the coils due to high 
pressure. 

Tlie Blow-off Valve. — The blow-off valve should be very tight, or 
there will be danger of its leaking every night, and thus emptying the boiler. 
It should enter the boiler so low down as to drain all the water when neces- 
sary. It should have a reliable valve, and should have its outlet in view, 
so that any leak in the valve can be seen. It must not be forgotten to close 
the blow-off. 

Boiler and Pipe Covering. — No reputable engineer will allow his 
boiler and pipe to remain uncovered, for he is reducing the capacity and the 
duty of both engine and boiler by allowing the waste of heat by radiation. 
There are many kinds of coverings in the market ; those giving the best 
results employing a non-conducting material, with air space. In buying cov- 
ering for boiler and pipe, especially for the latter, take care to get one that 
will have as many as possible of the following points : Lightness, to save 
freight and to prevent weighing the pipes down ; ease of application and 
removal ; freedom from cracking and crumbling ; low heat-conducting 
power and low cost ; and it is perhaps an advantage if it can be put on the 



146 



BOILERS. 



pipes when they are hot. For low temperatures, such as occur on ordinary 
mill boilers, the Toope Sectional Covering, Fig. 62, made by Chalmers-Spence 
Company, N. Y., may be recommended. It consists of layers of hair felt, alter- 
nating with asbestos inside and out, being made in sections three feet long, 
split down one side so as to be easily applied, and the joint being fastened 
by wire staples or by copper wire, and then pasted over with paper. The 
covering should be larger than the pipe, and should be held off at an equal 
distance all around by short collars of the same material, breaking joint 
with the lengths. Fig. 63 shows another form of covering made by the 
same company, but not sectional. 




Fig. 62. — "Toope" Sectional Pipe Covering. 




Fig. 63. — "Air Space Boiler and Pipe Covering. 



Experiments made by the author with this covering on 2^ inch steam 
pipe of Newton Machine Tool Works, Philadelphia, and others, show as 
follows : 



- 


"0 

rt 4J 

<! 


Average Tempera- 
t u r e of Steam 
Pipe, Fahr. 


k hi 
^ c 

D-S 
H > 

OJ 

HO 
u 

> 

< 


)-< 

aa 

cj 

o32 
> 

< 


Relative Non-con- 
ducting Values of 
Covering. 


Asbestos and Hair Felt (Toope), ) 
I in. thick, i in. air space, . \ 


36^ 


268tV 


115* 


90 


I. 0000 


Asbestos and Hair Felt (Toope), ) 
I in. thick, no air space, . \ 


41^ 


264I 


I27i 


91 


0.8952 


Sectional Plaster, i in. thick, i in. ( 
air space, ) 


44 


259f 


I73f 


85 


7433 


Asbestos Ceinent, i in, thick, no > 
air space, j 


47tV 


270 


158,13 


9It5 


0.8039 



The figures given above are the averages of twelve readings. 



BOILER COVERINGS— BLOWERS. 147 

Blowers for Boilers. — A correspondent of the Boston Journal of 
Comf?terce, who had been investigating the subject of blowers for steam 
boilers, gives the following as the result : " From my investigation and 
experience I have arrived at the following conclusions : Upon inquiries at 
the largest manufactories, I found that there are more blowers now being 
used for boiler purposes than ever before, and that their use for that pur- 
pose is steadily increasing ; that the power required to run a blower for 
such purpose is small as compared with the benefits obtained in increased 
boiler capacity and the ability to use a cheaper class of fuel ; that there is 
small risk from fire if properly put up and used. During several years' 
use of a blower, and from inquiries made of those using for the same pur- 
pose, I can learn of no instance of back draught occasioned by its use. 
(The mill adjoining me using no blower, was set on fire by back draught.) 
There will be no blow-pipe action if the air is properly put into the ash pit ' 
and regulated by a gate, and the effect on the crown sheet will be the same 
as with strong natural draught. It is not an uncommon occurrence to be 
obliged to renew the crown sheet when blowers are not used. Certainly 
something must be wrong and out of the usual course to be obliged to renew 
them on new boilers in so short a time. In conclusion, my own experience 
demonstrates that to offset the disadvantages of a blower, if any, a saving is 
made of fifty per cent, in fuel expenses by my ability to use a cheaper class 
of fuel, although I have a good natural draught from a loo-foot brick 
chimney." 

Heating and Filtering Feed-Water. — No matter what means are 
employed to feed a boiler, steam pump, power pump, or injector, it is 
essential that the feed be constant and exactly equal to the steam generation, 
and desirable for many reasons that it should be pure and hot. The heater 
has for its office reclaiming from the gases of combustion, or from the 
exhaust steam, heat which would otherwise pass off unutilized. To change 
one pound of water at 32° into one pound of steam at 60 pounds pressure 
on the gauge (or 75 pounds total at 307-!°) requires 1 175.2 heat units. From 
water 28° degrees hotter, or 60° F., it takes only 1 147.2 units. If we could 
feed in water at 200°, we would gain another 140 units, requiring only 
1007.2 in all. Where exhaust steam can be used for this purpose, it is so 
much clear saving in coal, to say nothing of other advantages, such as 
avoidance of sudden chilling of the contents of the boiler and contractions 
of its shell, &c. The table on following page shows the percentage of sav- 
ing in fuel by heating feed-water, in raising steam at 60 pounds.* 

Fresh water feed is either soft — that is, nearly pure, as shown by its leav- 
ing no deposit on being evaporated on a plate of glass — or hard, that is, 
containing in solution mineral substances, as carbonate of lime (chalk, lime- 
stone, marble), or sulphate of lime, sulphate of magnesium, salt, &c. Feed- 
water may also contain in suspension undissolved matter, as mud, sawdust, 

* Engineer Nystrom, in his work on Steam Engineering, page 54, places the saving of fuel by 
heating feed from 62° to 100°, at 4.4 per cent.; to 200°, at 17 per cent., and to 212°, at 18 per cent.; this 
being in the case of steam of eighty pounds boiler pressure, shown on the gauge ; but these figures 
represent the maximum, and do not cover the ordinary practise of feeding in the water leg, where the 
feed does not undo the work of evaporation. 



148 



BOILERS. 



sand, &c. The limy carbonates are the most widely spread and abundant, 
and when the dissolving water is heated to 212° they are precipitated, being 
generally deposited on the bottom and sides of the boiler shell and tubes, 
on the tops of the flues, and in water legs. For this reason tubular boilers 
should be avoided in lime water districts. This deposit causes leakage at 
seams, fracture at plate edges, overheating and softening, or even burning 
of the plates. The use of animal oils as cylinder lubricants where they are 
liable to get round into the boiler, via the feed heater, makes the deposit 
spongy and tough. The loss of heat by the accumulation of scale by this 
means is proved to be about as follows : 1-16" scale requires extra heat 
corresponding to 15 per cent, of fuel ; ^" scale requires extra heat corre- 
sponding to 30 to 60 per cent, of fuel ; ^" scale requires extra heat corre- 
sponding to 60 to 150 per cent, of fuel. The danger of explosion, the 
frequent priming and foaming of the boiler, causing grit to work over into 
and cut the steam chest, slide valve, cylinder and piston, and the frequent 
stoppages for repairs or examinations, render it extremely desirable to 
remove the cause of incrustation by filtering out mechanically-held impuri- 
ties and precipitating those chemically dissolved. If, now, we can have a 
device which will not only remove the undesirable foreign bodies, but, in 
so doing, effect an economy by heating the feed, we shall be largely the 
gainers. 



i 

II 


Initial Temperature of the Feed-Water. 


32° 


40° 


50° 


60° 


70° 


80° 


90° 


100° 


120° 


140° 

1:87 

3-75 
5.62 

7.50 

9-37 


160° 

1. 91 

3-82 

5-73 
7.64 


180° 

1.96 
3.93 
5-90 


200° 


60°.. 

80°.. 
100°.. 
120°. . 
140°. . 
160°.. 
180°.. 
200°. . 
220°. . 
240°. . 


2.39 
4.00 

5-79 
7.50 
9.20 
10.90 
12.60 
14.30 
16.00 
17.79 


1. 71 
3.43 
5.14 
6.85 

8.57 
10.28 
12.00 
'3-71 
15-42 
17-13 


0.86 
2.59 
4 32 
6.05 

7.77 
9.50 
11.23 
13.00 
14.70 
16.42 


1-75 

3-49 

5-23 

6.97 

8.72 

10.46 

12.20 

14.00 

15.69 


0^88 
2.64 
4.40 
6.15 
7.01 
9.68 
11-43 

13-19 
14.96 


1:78 
3-55 
5-32 
7-09 
8.87 
10.65 

12.33 
14.20 


0.90 
2.68 

4-49 
6.26 
8.06 

9-85 
11.64 

13-43 


1.80 
3.61 
5-42 
7-23 
9-03 
10.84 
12.65 


3-67 
5.52 

7 36 

9.20 

11.05 


1.98 
3-97 



Baragwanath's Feed-Water Heater. — There is no difference 
of opinion among engineers about the desirability of having pure feed-water 
and of having that feed-water hot ; but while all agree that the feed should 
be pure and hot, all are not agreed to the best method of heating and purify- 
ing, and few really think just how great the saving and advantage are. About 
this thing they do agree : that the purer a feed-water, the better it is, and 
that the hotter the feed, the greater the saving. It has been found that the 
best way to free the water from certain chemical impurities actually dissolved 
in it is to heat it to the boiling point. This is at least true of most waters, 
and especially true of those containing carbonates of lime and kindred chemi- 
cal substances. This heating may be done either by employing the waste 
heat of the gases of combustion, by using live steam, or by exhaust steam. 



HEA TING FEED- WA TER. 



149 



Sometimes it is done bypassing the feed-water through a coil running through 
or alongside of the combustion chamber. The best way is to employ the 
exhaust steam, if it can be used so as not to produce back pressure upon the 
engine. The mistake should not be committed of having the heater too 
small, and in every case there should be some arrangement by which the 




Exterior. 

Fig. 64. — Feed-Water Heater. 



Section. 



mechanical and chemical impurities may be collected when dropped, and 
blown off when desired. Under the head of incrustation and corrosion, 
we have shown the loss of fuel by allowing scale or sludge to collect in the 
boiler, to say nothing of the great danger to the boiler. The form of heater 
shown herewith (Fig. 64)*, known as the "Steam Jacket Heater and 

* Made by Baragwanath & Pim, Chicago. 



150 BOILERS. 

Purifier," consists of an outer shell, A A, with heads, D D, between which 
flues, C C C, extend. There is an outer jacket, E, leading a space, H, between 
it and the inner shell. Both the heater and the jackets are secured to bed 
plates, W W. There is a scum chamber, R, with proper blow-off, F F. The 
cold and impure feed-water is let in through the lower pipe and passed to 
the boiler through the upper pipe. The exhaust steam enters the chamber 
V V, through pipe, MM, and passing through the flues CCC, descends 
through the steam space H H H, passing off through the exhaust pipe K. 
P is a nozzle for reaching the plate N. The condensed water falls to the 
bottom, and may be removed by the drip-cock S, although it would be 
much better if it were to be mingled with the feed, except in those cases 
where the cylinder is lubricated with animal oil, in which case the con- 
densed steam should not be allowed to enter the boiler. 

Feed-water is most liable to be muddy in the spring and fall, when 
there is more surface and muddy water running in and mixing with it. In 
the West the feed-water makes more scale in dry weather than in wet, as it 
contains less rain water. One of the muddiest sources of feed-water is the 
Chicago river and its tributaries. In the northern part of Wisconsin and 
the Lake Superior region the water is soft. 

Corrosion. — It frequently happens that where water is too pure to 
form any scale in boilers, it contains acid impurities rather than salts. 
These impurities cause internal corrosion. Besides, external corrosion takes 
place from many causes, as setting in too much impure lime, setting on damp, 
undrained foundation, allowing cold ashes to remain in contact with the 
iron, &c. Where wood is freely used the soot in the tubes and flues gets 
charged with pyroligneous acid, as is also the case where coal is freely 
changed. Sulphurous coal also corrodes the external surfaces. Corrosion is 
sometimes caused by galvanic action of brass connections attached directly 
to the iron shell, and this is hastened by leakage at their junction. It is 
proved beyond all question that perfectly pure water rapidly corrodes boilers, 
especially those of wrought iron. A most common cause of corrosion, as 
well as of other evils, is the introduction of animal oils, such as work in with 
the exhaust steam through the feed heater, and from jet condensers oleic 
acid is formed and attacks and dissolves iron, especially where lime is 
present to form a soap which sticks to the boiler walls. 

External corrosion is generally caused by the exposure of boilers to the 
weather, sometimes from leaky joints, droppings, and carelessness in allow- 
ing the water to run down underneath on blowing down, particularly when in- 
ternally fired. All of these wear away the boiler and shorten its life. Where 
boilers are entirely bricked in, external corrosion is hard to detect. Wood 
ashes should never be allowed to touch the boiler plate, especially on top, 
as any water dripping through leaches out a destructive alkaline salt. 
Ashes should not be allowed to accumulate, particularly in internally fired 
boilers. They are bad enough when dry, worse when wet. To prevent 
external corrosion it should be seen that the boiler seams and man-hole 
plates are tight, and that all attachments and steam pipes are free from 
leaks. Internal corrosion looks very much like ordinary rust. If a boiler 



CORROSION— GROOVING— INCRUSTATION. 151 

is covered with scale there are apt to be red streaks wherever there is a 
crack. 

Internal corrosion attacks the edges of plates at the joints and at the 
rivets. Sometimes it shows itself as a pitting of the plates like small-pox. 
It is very uneven in its action. When found in connection with scale, the 
boiler should be kept free from scale and as clean as possible by blowing 
the water out. If there is free acid in the water, the water should be aban- 
doned. If this cannot be done, the acid should be neutralized by some 
harmless alkali, as soda or soda ash, introduced with the feed. This should 
be used only where the water is acid, and where it is used the boiler should 
often be inspected to see that there is no harm being done by the combina- 
tion of the alkali with other things in the water. 

Grooving. — This is found running parallel with the lengths of the 
seams, close to the edge of the inner lap, also following the inner lap of girth 
seams. It results, in most cases, from straining and fretting the iron where 
there is unequal expansion in connection with impure feed-water, the skin 
getting cracked and the water attacking the inner layers of the plates. This 
cracking may be caused by improper setting or by unequal heating. There 
is more trouble from this cause where there is imperfect circulation. 

Incrustation. — When water contains only three per cent., by weight, 
of saline matter, no deposit takes place at the boiling point, under atmos- 
pheric pressure or at 212°. When it contains ten per cent., it deposits lime, 
principally sulphate. Common salt is deposited when there is 29.5 per cent. 
of it. At high temperatures, deposit takes place at less per cent. This is 
one reason why marine boilers have to carry low pressure, expanding at low 
temperature. In marine boilers there is great loss of heat by blowing off. 
If the water entering the boiler is at a density of 1.32, and that of the boiler 
maintained at 2.32, one part will be made into steam and one part will be 
blown out. If the water enters the boiler at 100° F., and the water is at 248" 
at each temperature, the total heat is 1189.58°, then there will be 1089.58° to 
be got from the fuel, and there will be 148° lost by blowing off. The loss is 

1089.58+148° 

— = 11.95 per cent. 

148° 

The lower the density, the less the loss by blowing off, and vice versa. 

To knock the scale off of the places which are within reach, sharp-faced 
scaling hammers are used, and long scaling bars, flattened at both ends, to 
reach more distant places. Scaling boilers, by heating up high with shavings 
and then pumping in cold water, is highly injurious, and causes leaks. To 
lessen corrosion from soot in the flues, as well as to increase the duty and 
lessen the fuel consumption, the flues should be swept. This is a very dis- 
agreeable operation, unless the soot and ashes are first sprinkled with water. 
If you consider the large amount of water evaporated in a long run of a 
boiler, and the great amount of scale or sediment that it will contain, the 
Croton water is comparatively pure ; but a 100 horse-power boiler which 
evaporates 30,000 lbs. of water in ten hours, will, in one month, evaporate 
390 tons, in which there will be 88 lbs. of solid matter. In many kinds of 



152 BOILERS. 

spring water there will be, or in this 390 tons, as much as 2,000 lbs. of solid 
matter. The Railroad Master Mechanics' Association of the United States 
estimates that the loss of fuel, cost of extra repairs, &c., due to incrustation, 
amount to an average of $750 per year for every locomotive in the Middle 
and Southern States. 

Characters of Scales. — Carbonate of lime appears as chalk, common 
limestone and granular marble. As it percolates in the soil the carbonic acid 
dissolves it, making the water hard, but when the carbonic acid escapes, the 
lime begins to be deposited. Carbonate of lime usually deposits as a fine 
powder, forming a whitish slush or sludge with the water. Carbonate of 
magnesia behaves in about the same way. If in large quantities, carbonate 
of lime remains soft for some time, if not heated too high. If boilers are 
properly cooled before being blown off, the carbonate of lime will be found 
as a fine powder, but if blown off while the plates, brickwork and flues are 
greatly heated, the sludge becomes baked hard on the plates. Soft deposits 
injure the boiler as well as hard. When the water becomes saturated with 
this material, there is a resistance offered to the escape of the steam bubbles 
and to the free conduction of heat. The deposit collects upon the bottom, 
around the seams, and, in fire-box boilers, around the furnace sheets and 
around the water legs. Its presence is shown by leakage of the seams, frac- 
tures at the edge of the plates and in the line of the rivets, and by overheat- 
ing and consequent depression of parts of the plates where it rests. Where 
grease finds its way into the boilers this trouble is increased, hence open feed 
water heaters, into which the exhausted steam from the engines is discharged 
with no provision for separating or extracting the grease or lime from the 
water, are to be used with caution. Sulphate of lime is heavy, and hence is 
not long held in suspension. It deposits, forming one of the most trouble- 
some scales that is known. Scales having a reddish tint owe this to presence 
of salts of iron. Water from iron districts, and in the vicinity of mines, and 
on the sides of mountains gives this scale. Sometimes that from artesian 
wells yields it, sometimes it turns up where least expected, where it has per- 
colated through some iron bogs. This scale injuriously affects the iron plate. 
The water that gets behind it has the appearance of blood, and when the 
boiler thus " bleeds," the scaleshould be removed at once. When there is 
much trouble from carbonate of lime, frequent blowing down an inch or two 
will be of use. If the impurities show at the gauge cocks and fur them, the 
surface blow should be used. Never, under any circumstances, blow down a 
boiler when hot and under working pressure. It ought to be enough to say 
this, but perhaps it will be better to state the reason why, under these cir- 
cumstances, a quantity of the suspended impurities lodges on the tubes and 
flues and finds its way into the water legs, then it burns, forming a hard scale 
that must be chipped off with hammer, chisel and pick. There are many 
boilers in which the scale has been formed entirely by reason of injudicious 
blowing down. They should be let cool ; the fires should be drawn, the fur- 
nace doors opened, till all is well cooled down — then the blow may be opened 
The slush or sludge should then be removed, and the boiler washed out with 
a hose. 



SCALE— FLUE CLEANERS. 153 

There are substances employed in removing or preventing scale which 
are effective in doing this, but injure the water. Among these we may class 
the barks of oak, hemlock, &c., sumac, catechu, logwood, &c. They will 
remedy scale in waters containing carbonates of lime or of magnesia, but 
they are injurious to the iron. It must be remembered that well waters 
containing bicarbonate of lime may be made to deposit this mineral by 
simply heating them to 212°. This process has no effect upon any other 
kind of impurities. We find molasses, cane juice vinegar, fruits, distillery 
slops, &c., used with success as far as removing the scale is concerned, but 
the acetic acid which they contain, and which is the active principle in 
removing the scale, is even more injurious to the iron than tannic acid. The 
action of soda ash with water containing sulphate of lime is to convert 
it into carbonate, which gives a scale easily cleaned. If used in excess it 
causes foaming, especially where there is oil coming from the engine, in 
which case they form soap. Petroleum has been recommended for waters 
which contain sulphate of lime, but unless very well refined it forms a crust. 
It is well, however, to purchase a regularly manufactured anti-incrustator, 
such as that made by George W. Lord, 3 16 Union street, Philadelphia. 
Potatoes and slippery elm are of use in many cases, as the starch or gummy 
matter which they contain envelops the solid particles and throws them 
down. The action is analogous to the clearing of coffee by the white of an 
egg. Catechu and other astringents are of use in limy water, but where they 
are used frequent blowing and surface blowing is necessary, otherwise the 
iron will be injured. Crude petroleum, that is, unrefined earth oil, is quite 
good for water containing sulphate of lime, but not so good against car- 
bonate of lime. When such purgers are used, the boiler should be often 
opened and cleaned, because scale lying in a heap upon the bottom of a 
boiler tends to ruin the boiler almost as much as if baked on hard. 

In asking expert advice as to scale in your boilers, or in ordering in- 
crustators, you should give the following details and send the sample of 
boiler scale — enough to cover a " nickel " is sufficient. If you have no 
sample of scale describe the nature of it. Send also a rough sketch of the 
boiler, showing the fire end of the boiler (if horizontal), also the exact location 
of the blow-off pipe, and how it is arranged. Particulars are of importance in 
giving proper advice. Details : How many boilers ; what kind of boilers ; 
horse-power of each boilc; ; entire boiler capacity ; how much steam you 
carry ; if the boilers have plenty of steam room ; what is the character 
and source of the feed-water ; how often you change water and get rid of 
sediment; where the blow-off is; how often you open the blow-off; how 
long you keep it open ; thickness of the boiler scale ; if the scale is very 
hard ; if it is closely formed, or porous ; if you feed from a tank ; if you 
use a heater — if so, what kind of a heater ; if the feed-pipe clogs up or 
forms a scale ; what kind of fuel you use ; if you run day and night, and if 
you run seven days in the week. A bottle of the water should be sent if 
possible. 

Flue Cleaners. — Flues should be kept cleaned from soot and fine ashes, 
which not only prevent the proper passage of heat to the water on the other 



154 BOILERS. 

side, but cause corrosion by reason of the acids that they contain, especially 
where wood is used as fuel. A convenient form is that made by the Chal- 
mers-Spence Company, N. Y., and shown in Fig. 65. It will be seen that it 
can be readily adjusted to tubes of different diameters. The working parts 
are of steel, and it should do better work than brushes. 

Management. — Perhaps there is not enough attention paid about the 
mill to the exactness of how long the boilers and engine are to last in good 
condition. It is one thing to get as much steam from as little grate surface 
and heating surface as possible, and another to keep the boiler for ten 
or fifteen hours in good condition. There are many boilers that are 
forced so much that they soon give out. Sometimes a little is saved in 
original outlay for boilers, or perhaps in the matter of fuel, but in many 
cases this is saving at the spigot and wasting at the bung-hole. 

To cool down an overheated boiler, the ordinary and incorrect way is 
to open the furnace doors, and if the water is low to start the pump. This 
causes sudden cooling of the plates, tubes and flues, and renders them 
liable to fracture, especially riveted joints from the rivet hole to the edge 
of the plate and along the line of rivets from hole to hole. 

It sometimes happens that, after the fires are covered for the night, the 
pressure in the boiler rises and opens the valves. This is caused by the 
hot masonry imparting its heat to the boiler. 

Boiler fittings and appliances are apt to get into very unreliable con- 




FiG. 65. — Flue Cleaner. 

dition from negligence, An ignorant man who expects that, when the 
water gets low m his boiler, the whistle will blow and a pump start automat- 
ically, will get into the habit of depending upon these signs, and some day 
the signal will fail to be given, and damage or disaster will result. 

Rules for the Management of Steam Boilers.— Engineers and 
users of steam power will be benefited by keeping constantly in mind the 
following rules : 

1. Condition of the Water. — The first duty of an engineer, when he 
enters his boiler-room in the morning, is to ascertain how many gauges of 
water there are in his boilers. Never unbank nor replenish the fire until this 
is done. Accidents have occurred, and many boilers have been entirely 
ruined from neglect of this precaution. . 

2. Low Water. — In case of low water, immediately cover the fire with 
ashes ; or, if no ashes are at hand, use fresh coal. Do not turn on the feed 
under any circumstances, nor tamper with, nor open the safety valve. Let 
the steam outlets remain as they are. 



MANAGEMENT OF STEAM BOILERS. 155 

3. In Case of Foaming — Close the throttle, and keep closed long 
enough to show the true level of water. If that level is sufficiently high, 
feeding and blowing will usually suffice to correct the evil. In case of 
violent foamings, caused by dirty water, or change from salt to fresh, or vice 
versa., in addition to the action above stated, check draft and cover fire with 
fresh coal. 

4. Leaks. — When leaks are discovered, they should be repaired as soon 
as possible. 

5. Blowing Off. — Blow down, under a pressure not exceeding 20 lbs., 
at least once in two weeks ; every Saturday night would be better. In 
case the feed becomes muddy, blow out six or eight inches every day. Where 
surface blow-cocks are used, they should be often opened for a few moments 
at a time. 

6. Filling up the Boiler. — After blowing down, allow the boiler to be- 
come cool before filling up again. Cold water pumped into hot boilers is 
very injurious, from sudden contraction. 

7. Exterior of Boiler. — Care should be taken that no water comes in 
contact with the exterior of the boiler, either from leaky joints or other 
causes. 

8. Removing Deposit and Sediment. — In tubular boilers the hand-holes 
should often be opened, and all collections removed from oyer the fire. Also, 
when boilers are fed in front and blown off through the same pipe, the col- 
lection of mud or sediment in the rear end should be often removed. 

9. Safety Valves. — Raise the safety valves cautiously and frequently, 
as they are liable to become fast in their seats and useless for the purpose 
intended. 

10. Safety Valve and Pressure Gauge. — Should the gauge at any 
time indicate the limit of pressure, see that the safety valves ^re blowing off. 

11. Gauge Cocks, Glass Gauges. — Keep gauge cocks clear and in con- 
stant use. Glass gauges should not be relied on altogether. 

12. Blisters. — When a blister appears, there must be no delay in having 
it carefully examined and trimmed or patched, as the case may require. 

13. Clean Sheets. — Particular care should be taken to keep sheets and 
parts of boilers exposed to the fire perfectly clean ; also all tubes, flues and 
connections \vell swept. This is particularly necessary where wood or soft 
coal is used as fuel. 

14. General Care of Boilers and Connjections. — Under all circum- 
stances keep the gauge cocks, &c., clean and in good order, and things gen- 
erally in and about the engine and boiler-room in a neat condition. 

The A7nerican Machinist puts the following 

Pertinent Q,uestions : — How long since you were inside of your 
boiler ? Were any of the braces slack ? Were any of the pins out of 
the braces ? Did all the braces ring aHke ? Did not some of them sound 
like a fiddle string ? Did you notice any scale on flues or crown sheet ? If 
you did, when do you intend to remove it ? Have you noticed any evidence 
of bulging in the fire-box plates ? Do you know of any leaky socket bolts ? 
Are any of the flange joints leaking ? Will your safety valve blow of itself, 

11 



156 BOILERS. 

or does it stick a little sometimes ? Are there any globe valves between the 
safety valve and the boiler ? They should be taken out at once, if there are. 
Are there any defective plates anywhere about your boiler ? Is the boiler so 
set that you can inspect every part of it when necessary ? If not, how can 
you tell in what condition the plates are ? Are not some of the lower courses 
of tubes or flues in your boiler choked with soot or ashes ? Do you abso- 
lutely know, of your own knowledge, that your boiler is in safe and economi- 
cal working order, or do you merely suppose it is ? These are questions of 
great importance. 



^*|^ 



CHAPTER X. 

THE STEAM ENGINE. 

Steam — Mechanical Effect — Expansion — Throttling and Wire-Drawing — Back Pressure — Economy 
of High-Pressures — Condenser — Compression — Speed — Superheated Steam — Steam Jacket — 
Lagging — Governor — Gardner's Governor — Foundation — Steam Cylinders — Fly-Wheel — 
Stroke — Steam Chest— Area of Steam Ports — Piston Head — Piston Rod — Slides — Cross- 
Head— Connecting Rod — Crank Pin — Crank — Piston-Head Packing— Piston-Rod Pack- 
ing — Care of Steam Engine — Pounding — Cylinder Lubrication — Indicator Diagrams and, 
Expert Tests — Wheelock Engine — Computation of Horse-Power — Power and " Duty " — Cost 
of Putting in Steam Power — Cost of Fuel per Barrel of Flour. 

Steam is a light elastic fluid, generated from the evaporation of any 
liquid by the application of heat, although the term is generally restricted to 
vapor of water, generated during a state of ebullition. The air which sur- 
rounds the earth presses upon its surface with an average weight equal to 
14.7 pounds per square inch at the level of the ocean. This pressure is 
balanced by a column of mercury, 29.9212 inches in height. At higher 
altitudes this pressure is, of course, less, by reason of the lesser height of the 
air column. Under 14.7 pounds absolute pressure per square inch, fresh 
water boils at a temperature or sensible heat which marks 212° F. on the 
thermometer. To raise water from the freezing to the boiling point takes 
a certain time and a certain amount of fuel, and the application of more 
heat after the boiling has commenced produces gradual evaporation, taking 
more time and fuel to change it all into steam than to raise it from the 
freezing to the boiling point. This extra heat is absorbed by the water, 
and retained by it as long as it remains steam. The thermometer does 
not show it, so it is called latent heat. When the steam becomes again 
condensed into water, all of this latent heat is given back and becomes again 
sensible. If water is used to condense steam, the condensing water becomes 
hot, that is, shows sensible heat by absorbing the latent heat of the steam. 
Neither the sensible heat nor the latent heat, nor their sum, remain constant, 
but vary with the pressure. The table from Regnault, which will be found 
on the following page, gives the degrees of heat contained in saturated 
steam, in Fahrenheit degrees of heat and in English inches. 

Mechanical Eflfect. — Take a cylinder of one square inch in area of 
cross section, fitted with a steam-tight, easy fitting piston. Put one cubic 
inch of water in the bottom of this cylinder and apply heat below. When 
the temperature of the water gets to be 212° F., it will boil, the piston 
will rise gradually, and if the cylinder is long enough it will rise to the 
height of 1641.5 inches, showing that the steam took up 1641.5 times the 
volume of the water from which it was generated. Thus the evaporation of 
one cubic inch of water will raise 14.7 pounds 1640.5 inches or 136.7 feet 
high, or do 14.7 x 136.7 =2009.49 foot pounds of work. We are supposing 



158 



THE STEAM ENGINE. 



that there is no friction to overcome, and that the piston has no weight. 
Allowing the steam to condense in the tube, the atmospheric pressure will 
force back the piston to its original position on the top of the cubic inch of 
water, and the work done by the steam may thereby be undone, or, additional 
equivalent work done. 

Expansion. — "Working steam expansively" is letting it into the work- 
ing cylinder and cutting it off before the piston has completed its stroke, 
making less than a cylinder full of steam, by its expansive force, do more 
work than the same weight of steam would do if allowed to follow a piston 
under full boiler pressure. Taking a model cylinder of a condensing 
engine, two units in length and one in cross-section, admitting steam into it 
and cutting the steam off when the piston has made only half a stroke, that 
is, a stroke of only a unit in length, we will have, as the work done during 
the first half-stroke, i x i x i, that is, piston area times pressure times distance 
equal to one, for the work performed during the time when the steam was 
under full pressure. During the second half-stroke, however, in which the 
steam is expanding from a high pressure to a low one, we have a work done 
equal to i x i x 0.69, that is, area times distance times mean pressure. The 
total work throughout the stroke thus equals 1.69. If, instead of expanding 
against the piston during the second half-stroke, we had exhausted the steam, 
the total work performed would only have been one instead of 1.69, although 
the steam consumed would have been the same quantity, so, by cutting off at 
half stroke we get 0.69 more work out of the same steam. If we had used 
steam at full pressure during the whole of the stroke, we would have got 
two units of work, but we would have used two volumes of steam. So it 
must be understood that in using steam expansively we do not get more work 
out of a given cylinder than if we used steam at full pressure throughout 



REGNAULT'S EXPERIMENTS. 

Degrees of Heat contained in Saturated Steam, in Fahrenheit Decrees of Heat and 

English Inches. 



lire of 
d Steam 
Point of 
tionj. 


Corresponding 
Elastic Force. 


latent 
sensible 

iheit. 


ure of 
d Steam 
Point of 
tion). 


Corresponding 
Elastic Force. 


latent 
sensible 
ove 
iheit. 


mp:rat 
aturate 
r at the 
ndensa 






1 heat 
plus 

leat ab< 
Fahrei 


mperat 
aturate 
r at the 
ndensa 






1 heat 

plus ! 

eat ab 

Fahrei 










uc/5 .9 


In 


In Atmos- 




<U[/3 


In 


In Atmos- 


o| ° 


l> 


Inches. 


pheres. 


h.S 


l> 


Inches. 


pheres. 


Hx 


" Fahr. 








° Fahr. 








32 


O.1811 


0.006 


1123.70 


248 


58.7116 


1.962 


1189.58 


50 


0.3606 


0.012 


II29.IO 


266 


79.9321 


2.671 


1194.98 


68 


0.6846 


0.023 


1134.68 


284 


106.9930 


3-576 


1200.56 


86 


I. 2421 


0.042 


II40.16 


302 


140.9930 


4.712 


1205.96 


104 


2.1618 


0.072 


1145.66 


320 


183.1342 


6.120 


1211.54 


122 


3.6212 


0.I2I 


1 15 1. 06 


338 


234.7105 


7.844 


1216 94 


140 


5-8578 


0.196 


1156.64 


356 


297.1013 


9.929 


1222.52 


158 


9.1767 


0.306 


1162.04 


374 


371.7590 


12.425 


1227.92 


176 


13.9621 


0.466 


1167.62 


392 


460.1943 


15-380 


1233.50 


194 


20.6869 


0.691 


1173.02 


410 


560.9673 


18.84S 


1238.90 


212 


29.9212 


1. 000 


1178.60 


428 


684.6584 


22.882 


1244.48 


230 


42.3374 


1-415 


1184.00 


446 


823.8723 


27-535 


1249.88 



MECHANICAL EFFECT— EXPANSION. 



159 



the whole stroke, but we get more work out of a given amount of steam, con- 
sequently more work with a given amount of fuel. Thus, by making our 
engines large enough to use steam expansively, we are able to use less fuel to 
do a given amount of work. This 69 per cent, gain does not represent the exact 
gain in fuel ; what this is we will explain further on. The spaces occupied 
by steam are inversely as the pressures, thus, if steam at 60 lbs. abs., in a 
given volume, is allowed to expand into double the space, it will have thirty 
lbs. abs. pressure; if into three times the space, twenty lbs. abs. pressure; into 
four times the space, fifteen lbs. abs. pressure ; into five times the space, 
twelve lbs. abs. pressure, and so on. We can approximately calculate the 
pressure in a given cylinder under any degree of expansion by supposing it 
to be divided into a number of equal parts, say eight, getting a pressure at 
each of these points and averaging it. Suppose that we cut off at .half stroke,' 
the j^ressure at each division mark during the half stroke would be one ; at 
the fifth division, 4-5 or .8 ; at the sixth, 4-6 or .666 ; at the seventh, 4-7 or 
.5714 ; at the eighth, 4-8 or 0.5. At this point it will be seen that the steam 
occupies double the volume that it did before it was cut off, and has half the 
pressure. Now, if we add the four last pressures together, and divide by 
four, we will get the mean pressure during expansion, and the mean pressure 
during the whole of the stroke will be found by adding the eight pressures 
together and dividing by eight. The average pressure during the expansion 
will be .6345, and the average during the whole stroke, 0.8172. The following 
tables give the ratio of pressures to point of cut-off at any desired point. 

ACTUAL EXPANSION RATES; RELATIVE ADMISSION PERIODS, PRES- 
SURES AND PERFOR.MANCE, ALLOWING REGULAR EXPANSION, 
AND NO WIRE-DRAWING NOR THROTTLING. 



Actual Ex- 




Period of 








Rates of 


Hyp. Log. 


Admission 


Average 


Total 


Total 


Performance 


pansion. 

Initial 

Voluine=i. 


of Actual 


Allowing 


Total 


Initial 


Final 


of Equal 


Exp. Rate. 


Clearance of 
7 ^ of Stroke. 


Pressure. 


Pressure. 


Pressure. 


Weights of 
Steam. 


I.b 


.000 


ICO. 


1. 000 


1. 000 


1. 000 


1. 000 


I.I 


•0953 


90-3 


.096 


1.004 


.gog 


1.096 


1. 18 


.1698 


83-3 


.986 


1. 014 


.847 


1. 164 


1.23 


.2070 


80.0 


.980 


1.020 


.813 


1.206 


1-3 


.2624 


75 3 


.969 


• 1.032 


-769 


1. 261 


1-39 


.3293 


70.0 


•953 


1.049 


.719 


1^325 


1-45 


.3716 


66.8 


•942 


1.062 


.690 


1^365 


1-54 


•4317 


62.5 


.925 


T.oSi 


-649 


1.425 


1.6 


.4700 


59-9 


.913 


1-095 


.625 


1. 461 


1.88 


■6314 


50.0 


.860 


i^i63 


•532 


1. 6x6 


2.28 


.8241 


40.0 


.787 


1. 271 


•439 


1^793 


2.4 


■8725 


37.6 


.766 


1-305 


.417 


i-837 


2.65 


■9745 


33-3 


.720 


1-377 


•377 


1^925 


2-9 


1.065 


29.9 


.692 


1-445 


• 345 


2.006 


3-35 


1.209 


25.0 


.637 


1-570 


.2g8 


2.129 


4- 


1.386 


19-7 


.567 


1.764 


.250 


2.278 


4-5 


1.504 


1 16.8 


.526 


i.goi 


.222 


2.370 


5-5 


1-705 


i 12.5 


•457 


2.188 


.182 


2.511 


5-9 


1-775 


II. I 


.432 


2.315 


.169 


2.556 


6.3 


1. 841 


10. 


•413 


2.421 


•159 


2.597 



160 



THE STEAM ENGINE. 



In using steam expansively, we must, of course, commence with a greater 
pressure than if we are using it full stroke, because we must obtain the same 
mean pressure. Taking, for example, an engine using a steam pressure of 
60 lbs. abs. per square inch full stroke, how much must that pressure be 
increased to work the same engine with steam expanded twice and obtain 



TABLE OF HYPERBOLIC LOGARITHMS. 





Hyper- 




Hyper- 




Hyper- 




Hyper- 




Hyper- 


No. 


bolic 


No. 


bolic 


No. 


bolic 


No. 


bolic 


No. 


bolic 




Log. 




Log. 




Log. 




Log. 




Log. 


1.05 


.049 


305 


1. 115 


5.05 


1. 619 


7.05 


1-953 


905 


2.203 


I.I 


.095 


3 


I 


1-131 


5-1 


1.629 


7 


.1 


1.960 


9 


I 


2.208 


1. 15 


.140 


3 


15 


1. 147 


5-15 


1.639 


7 


15 


1.967 


9 


15 


2.214 


1.2 


.182 


3 


2 


1. 163 


5-2 


1.649 


7 


2 


1.974 


9 


2 


2.219 


1-25 


.223 


3 


25 


1. 179 


5-25 


1.658 


7 


25 


1.981 


9 


25 


2.225 


1-3 


.262 


3 


3 


1. 194 


5-3 


1.668 


7 


3 


1.988 


9 


3 


2.230 


1-35 


.300 


3 


35 


1.209 


5-35 


1.677 


7 


35 


1-995 


9 


35 


2.235 


1.4 


.336 


3 


4 


1.224 


5-4 


1.686 


7 


4 


2.001 


9 


4 


2.241 


1-45 


.372 


3 


45 


1.238 


5-45 


I.6g6 


7 


45 


2.008 


9 


45 


2.246 


1-5 


.405 


3 


5 


1-253 


5-5 


1-705 


7 


5 


2.015 


9 


5 


2.251 


1.55 


.438 


3 


55 


1.267 


5-55 


1. 714 


7 


55 


2.022 


9 


55 


2.257 


1.6 


.470 


3 


6 


1. 281 


5.6 


1.723 


7 


6 


2.028 


y 


6 


2.262 


1.65 


.500 


3 


65 


1-295 


5-65 


1.732 


7 


65 


2.035 


9 


65 


2.267 


1-7 


.531 


3 


7 


1.308 


5-7 


I- 740 


7 


7 


2.041 


9 


7 


2.272 


1-75 


.560 


3 


75 


1.322 


5.75 


1-749 


7 


75 


2.048 


9 


75 


2.277 


1.8 


.588 


3 


8 


1-335 


5.8 


1.758 


7 


8 


2.054 


9 


8 


2.282 


1.85 


.615 


3 


85 


1.348 


5-S5 


1.766 


7 


85 


2.061 


9 


85 


2.287 


1.9 


.642 


3 


9 


1. 361 


5-9 


1-775 


7 


9 


2.067 


9 


9 


2.293 


1.95 


.668 


3 


95 


1-374 


5.95 


1-783 


7 


95 


2.073 


9 


95 


2.298 


2. 


.693 


4 




1-386 


6. 


1.792 


8 




2.079 


10 




2.303 


2.05 


.718 


4 


.05 


1-399 


6.05 


1.800 


8 


05 


2.086 


15 




2.708 


2.1 


.742 


4 


I 


1. 411 


6.1 


1.808 


8 


I 


2.092 


20 




2.996 


2.15 


.765 


4 


15 


1-423 


6.15 


1. 816 


8 


15 


2 098 


25 




3.219 


2.2 


.788 


4 


2 


1-435 


6.2 


1.824 


8 


2 


2.104 


30 




3.401 


2.25 


.811 


4 


25 


1-447 


6.25 


1-833 


8 


25 


2. no 


35 




3.555 


2-3 


.833 


4 


3 


1-459 


6.3 


1. 841 


8 


3 


2. 116 


40 




3.689 


2-35 


.854 


4 


35 


1.470 


6-35 


I 848 


8 


35 


2.122 


45 




3.807 


2.4 


, .875 


4 


4 


1.482 


6.4 


1.856 


8 


4 


2.128 


50 




3.912 


2.45 


.896 


4 


45 


1-493 


6-45 


1.864 


8 


45 


2-134 


55 




4.007 


2.5 


.916 


4 


5 


I - 504 . 


6.5 


1.872 


8 


5 


2.140 


60 




4.094 


2-55 


■ 936 


4 


55 


I-515 


6.55 


1-879 


8 


55 


2.146 


65 




4.174 


2.6 


.956 


4 


6 


1.526 


6.6 


1.887 


8 


6 


2.152 


70 




4.248 


2.65 


■975 


4 


65 


I -.-^37 


6.65 


1.895 


8 


65 


2.158 


75 




4.317 


2-7 


•993 


4 


7 


1-548 


6-7 


1.902 


8 


7 


2.163 


80 




4.382 


2-75 


1.012 


4 


75 


1-558 


6.75 


1. 910 


8 


75 


2.169 


85 




4.443 


2.8 


1.032 


4 


8 


1.569 


6.8 


1. 917 


8 


8 


2.175 


go 




4.500 


2.85 


1.047 


4 


85 


1-579 


6.85 


1.924 


8 


85 


2.180 


95 




4.554 


2.9 


1.065 


4 


9 


I 589 


6.9 


1-931 


8 


9 


2.186 


100 




4.605 


2-95 


1.082 


4 


95 


1.599 


6.95 


1-939 


8 


95 


2.192 


1,000 




6.908 


3- 


1.099 


5- 


1.609 


7- 


1.946 


9- 


2.197 


10,000. 


9.210 



the same power ? The mean pressure of steam expanded to double its 
volume is 84-j per cent, of the initial pressure, and consequently 60 -^ 
0.845 ^71 lbs. abs. per square inch, which is the steam pressure required. In 
the first case we used 60 lbs. abs. full stroke, and in the second 71 lbs. abs. 
half stroke, which makes an economy of (60 — -y- ) ^— 60 = 0.41 nearly, or 



THROTTLING AND WIRE DRAWING. 161 

41 per cent. gain. In practice, about one-half of this saving is neutralized by 
various sources of loss connected with the boiler. 

This does not mean 41 per cent, less fuel put in the furnace, but 41 
per cent, of that which reaches the cylinders, lessened by a slight con- 
densation due to expansion. There is, of course, a loss from part of the 
fuel not being combustible and part of it going out of the chimney in the 
shape of heat to produce draft, part lost by radiation, part lost by condensa- 
tion in the pipes, &c., so that the actual saving in cutting off at half stroke 
is more nearly 20 per cent, than 41 per cent., and this should not be con- 
founded with the 69 per cent, of theoretical increase of work done by the 
same weight of steam over what it would have done had it not been 
cut off. 

When we say " quantity of steam " we always mean weight of steam,- 
unless volume is distinctly stated. 

We can represent the pressure which the steam has at any point in the 
cylinder very nicely by means of diagrams representing so many pounds to 
the inch. If there was a perfect vacuum in the cylinder there would be no 
limit to expansion, but there really is a limit. There should be enough un- 
balanced at the end of the stroke to overcome the friction of the engine. If 
there is three pounds back pressure above atmosphere and one and a half 
pounds friction, there must be at least six pounds pressure above atmosphere 
at the end. For non-condensing engines, the calculations are made the 
same way as for condensing, always remembering to add to the initial 
pressure, shown on the gauge, which is pressure above atmosphere, 14.7 lbs. 
for calculation based on performance at the sea-level. In higher districts, 
the atmospheric pressure is less — say 14.5 lbs. in Ohio. The ordinary main 
valve of an engine should not cut off with lap and lead earlier than at f 
of the stroke, making \ stroke expansion or 1.33 nominal expansion rate ; 
and even then, the valve and valve gear must be carefully regulated, so that 
the exhaust will not open and close too soon. The main valve is some- 
times made to cut off earlier, but it does not regulate the steam econom- 
ically. 

Throttling and Wire Drawing. — When the steam used in the 
cylinder has its free access retarded by passage through a throttle valve, 
partly closed, it is said to be throttled. When steam is cut off very slowly 
by an ordinary slide valve, it is simply retarded, but the effect is called wire 
drawing. When a single eccentric is used, the earlier the cut off, the more 
the wire drawing. Wire drawing may be lessened by double eccentrics and 
slide, gridirons and so on. It is best avoided by the Corliss type of gear, 
by which the steam valves are opened and closed suddenly by springs. 
Throttling and wire drawing are accompanied by direct loss, due to the slight 
friction which takes place during the process, and by indirect waste by 
reason of the increased proportion of work expended in overcoming back 
pressure. 

Wire-drawing is advantageous under some circumstances and disad- 
vantageous under others. Steam is heated by wire-drawing, and moisture 



162 THE STEAM ENGINE. 

in it is thus, to a certain extent, evaporated. When the steam is cut 
off at half stroke, or earlier, it is advantageous to wire-draw it through 
the slide valves or throttle valve, because it will then expand livelier and 
leave no water of condensation in the cylinder. But when the steam is 
admitted full stroke there is disadvantage in wire-drawing, because the steam 
will then leak, as it were, into the cylinder to nearly the full boiler-pressure 
at the end of the stroke, depending upon how fast the engine runs ; and 
thus much steam will pass through without doing full work. 

Back Pressure. — It is impossible in practice to get a perfect vacuum, 
or even a perfect outlet for the steam at the return stroke, consequently 
there is always a certain amount of steam in the cylinder opposed to the 
motion of the piston, causing what is called " back pressure." If we have an 
average pressure of 20 lbs. by gauge driving the piston forward, and a pres- 
ure of 4 pounds retarding the same, the mean effective pressure would be 
but 16 pounds, and that four pounds must be deducted from the working 
pressure in order to give the unbalanced pressure at the end of the stroke. 

Economy of High-Pressures, — The measure of the deficiency of 
a steam engine is the steam rejected, that is, the terminal pressure. The 
measure of the economy is the mean effective pressure less the average back 
pressure. Having a constant pressure to throw away, we want to get all out 
of it that we can. If Ave start with ten gauge pounds, = 24.7 lbs. absolute, 
and by cutting off at about one-sixth, expand to 5.3 gauge pounds terminal 
pressure = 20 lbs. above vacuum, we get a quantity of work equal to the 
band A, Fig. 66, or 9.3 pounds mean effective pressure. 




Fig. 66.— Scale for High-Pressure Steam Engine. 



BA CK PRESS URE— HIGH-PRESS URE— CONDENSER. 



163 



If we start with twenty gauge lbs. initial pressure, we get more work (which 
is represented by the band B) for nothing, raising the mean effective pressure 
to 16.3 pounds, or 76 per cent, gain at present. 100 gauge lbs. initial pres- 
sure is about the limit of present good and politic practice. The following 
table gives the water consumption, economy of fuel and gain of power : 







Lbs. Water 


Gain of Power 


Economy of 


Initial Pressures. 


M. E. P. 


per hour 


per increment 


Fuel per incre- 






per H. P. 


of 10 lbs. 


ment of 10 lbs. 


10 gauge lbs. 


9-3 


75-3 


Per Cent. 


Per Cent. 


, 20 " " . . 


16.3 


42.9 


76 


43 


30 '■ " . . 


2r.2 


33-0 


30 


23 


40 " " . . 


25.6 


27.3 


20 


17 


50 " " . . 


29.1 


24.0 


14 


12 


60 •' " . . 


32.0 


21.9 


10 


09 


70 " " . . 


34-5 


20.3 


08 


07 


80 " " . . 


36.3 


19.2 


06 


05 


90 " " . . 


38.1 


18.4 


05 


04 


100 " " . • 


39-2 


17.8 


03 


03 



Condenser. — There is a difference between absolute pressure and the 
ordinary nominal pressure which is indicated by pounds per square inch 
above that of the atmosphere. Water evaporated in the open air is at zero 
pressure instead of steam at 14.7 pounds per square inch, counterbalancing 
the atmospheric pressure. Such steam used in a condensing engine is said 
to be working " /;z vacuo." To distinguish the steam pressure above vacuum 
from that above atmospheric pressure, European engineers adopt the 
distinction ^^ over pressure" axid. ^'' under pressure." When steam of higher 
pressure is used, it is usual in calculating the horse-power to add the so- 
called vacuum to the so-called steam pressure. Now, to use a condenser 
is simply to remove an opposing force. The condenser is not a power 
generator. It simply enables all the work done by the steam in the cylinder 
to.be brought to bear upon the piston instead of some of it being wasted in 
pushing away atmospheric pressure. This does not mean that there is air 
on the other side of the piston, but that the steam on the exhaust side of the 
piston is pressed against the piston by the atmospheric pressure from without. 
In the condensing engine, this atmospheric pressure is almost entirely re- 
moved. The only force to oppose the steam pressure on the working side 
of the piston is the strain in the rod plus a pound or two of so-called "back 
pressure " in the condenser. If the condenser gave a perfect vacuum there 
would be none of this so-called back pressure ; but then there would be no 
pressure in the condenser to press out the condensing water through the foot 
valve of the pump. The simplest form of condenser is the " syphon con- 
denser" of which there are several styles. 

Compression. — Excessive compression of steam at the end of the 
exhaust stroke, is not advantageous, because it makes a back pressure on the 
crank pin before reaching the centre. It has been argued that the com- 
pression, generally called "cushioning," is advantageous by reason of fitting 
the clearance and causing a ready pressure for the near stroke ; but that 
advantage does not by far compensate for the back pressure on the crank 



164 THE STEAM ENGINE. 

pin. In very fast running engines it has been found by experience that 
strong cushioning is necessary to make them run smooth, but a little more 
lead of the main valve will answer the same purpose and better utilize the 
effect of the steam. 

Clearance has the advantage that it leaves a safety space between the 
piston head for preventing the piston from striking. The disadvantage of 
clearance is that the steam volume inclosed therein is lost for the effect of 
the engine when no expansion is used. But when the steam is expanded 
in the cylinder the clearance steam is also expanded and is thus partly 
utilized for work. The higher the expansion used, the more will the 
clearance steam be utilized. 

" Cut off at," means from the beginning of the stroke. The proportion 
of power utilized by the clearance steam, which may also include that in the 
steam port, is as follows : 

Steam cut off at f, f, \, f, ^, 
Per cent utilized, 46, 58, 69, 78, 95. 

Speed. — ^The tendency is to use short stroke and high speed of revolu- 
tion. Thus, instead of a 16 x 48 engine using 80 gauge lbs. of steam cut-off 
at one-quarter stroke, and making 60 revolutions, we can get the same power 
out of a 13 X 24 engine with the same pressure and point of cut-off, but run- 
ning 200 strokes per minute. The 13 x 24 engine costs much less than the 
16 X 48, and does the same work with the same fuel, but its life must be 
somewhat less by reason of the greater number of shocks of reversing at each 
end of the stroke. 

Superheated Steam. — Steam as first generated in a boiler contains a 
certain amount of water, or, in other words, is not dry. 

On being brought in contact with the heating surfaces this saturated 
steam will absorb heat from them, and thus the water in the steam will be 
evaporated, the steam becoming what is called dry. Dry steam is no hotter 
than saturated. After it becomes dry it may still absorb heat, and there 
being no more work for this extra heat to do in evaporating water, the steam 
becomes hotter, or superheated. Wet steam does not work economically in 
the engine ; dry steam is much more economical, and superheated steam is 
more economical than either. This economy has been calculated by Rankine 
and others. In an engine taking steam at thirty-four (34) pounds pressure 
above the atmosphere and expanding it to five times its original volume (in 
other words, cutting off at once one-fifth stroke) there will be an economy 
of 15 percent, by superheating steam from its former temperature of 257° to 
428°. If this superheating could be done by heat which would otherwise be 
wasted, instead of by heat, some of which might have been used in making 
saturated steam, the economy would be 23 per cent. 

Steam Jacket. — The steam jacket has, for its effect, to prevent con- 
densation in the cylinder by furnishing heat to the expanding steam. Wet 
steam is a rapid absorber of heat, and dry steam a slow one. On cylinders 
of great diameter and of very quick stroke the effect of the jacket cannot 
reach the middle of the cylinder quickly enough to prevent condensation. 
The result of the jacket is to get work from steam, which does not enter the 



SPEED— SUPERHEATED STEAM. 165 

cylinder, by condensing in the jacket instead of in the cylinder. Still the 
same amount of steam is condensed outside as there would be inside, perhaps 
a little more, because the film is thinner than the circumference of the jacket 
is larger than that of the cylinder. But very often we find that the jacket 
does not result in any economy of steam consumption, but increases the 
power of a small engine without changing the initial pressure or the rate of 
expansion. The steam jacket was at first applied around the body of the 
cylinder only, then to the end and cover, and some engineers have admitted 
steam to the piston. The larger the surfaces, the greater the advantages of 
a jacket. In speaking of jackets we always refer to the steam jackets and 
not to hot air jackets. 

Liagging. — Every steam cylinder should be lagged with wood, asbestos, 
mineral wool, felt, or other non-conductor of heat, to prevent radiation of ■ 
heat and condensation in the cylinder. 

Governor. — The centrifugal governor is of advantage in securing 
economy of fuel and approximate regularity of motion, but there are some 
peculiar defects which are insurmountable. Put in very plain English, in 
order for a centrifugal governor to work, the engine must go fast in order 
to go slow, or must go slow in order to go fast, since there cannot be a 
change of height of the balls without change of speed in the engine and 
balls. Again, the opening of the steam valve depends upon the angle 
between the arms of the balls and the central spindle around which they 
revolve. So, if we have an engine doing its full amount of work, the gov- 
ernor will keep at a uniform speed so long as the average resistance of the 
engine stays the same ; but, as soon as any work is taken off, the engine's 
speed will be increased by reason of the lessening of the work, and the 
engine will run uniformly enough at this higher speed so long as the work 
remains without further alteration, as the degree of opening the steam valve 
is determined by the angle to which the governor arms are raised by the 
velocity of the revolution. 

The steam valve can be moved only by a change of speed of the gover- 
nor balls and a consequent change of their angle of suspension, hence a 
larger supply of steam to do the increase of work can be got only in con- 
junction with a smaller angle of the governor arms ; and, secondly, with a 
slower speed, and in order to partly shut off steam to meet a reduction of 
work, the balls must have a higher speed in order to lift them to a greater 
angle. In order to make the governor sensitive it must have a high speed. 
The higher its speed in comparison with that of the engine, the more sensi- 
tive it is, because by this means whatever variation of speed there is in the 
engine is multiplied many times in the governor. However, the higher speed 
you get the more wear you get, and with wear comes lost motion, which is 
liable to cause trouble to the engineer and sudden variation in the speed of 
the engine. Another trouble is that the governor must have strength 
enough to do a certain amount of actual work holding and moving the valve, 
and it must work evenly and surelv, no matter whether the valve stem in 
its stuffing box or the valve itself sticks. This power can be got either by 
a very high speed with its attendant wear, or by very heavy balls, which 



166 THE STEAM ENGINE. 

make the device large, cumbersome and expensive. If the fly wheel is 
properly proportioned, there is less need of a sensitive governor than if it 
is made from a pattern on hand made for some other engine of entirely dif- 
ferent proportions, and working under entirely different conditions. In the 
Corliss engine the governor does not do any work, but simply shows where 
the cut-off is to be effected, and if the fly wheel is of proper weight and size 
it is attended with great regularity of speed and economy of fuel. 

A writer speaking of steam engine governor tests, says : " We are 
unaware of any reliable tests having been instituted as to the sensitiveness 
and correct working of steam engine governors, and still it would seem that 
this was desirable, especially to judge of the ef^ciency of new forms of gov- 
ernors. The subjoined brief outline of the kind of test necessary will, 
therefore, not be without interest. The object of a governor is to act on 
the throttle valve or cut-off mechanism in such a manner that when the load 
is increased more steam will be furnished to the engine, and when the load 
is diminished the supply of steam will be decreased to a corresponding 
extent, so that whatever the work to be done by the engine within certain 
limits, the number of revolutions are to remain practically uniform. To test 
whether this action takes place with a given governor, it becomes necessary 
to make two series of experiments, attaching the governor to the throttle 
valve and cut-off mechanism respectively. The engine, after noting the 
working of the governor, should be released from the greater portion of its 
work suddenly, and the length of time and number of revolutions occupied 
by the engine in recovering itself noted. Indicator cards should be taken 
before the work is thrown off, and after the engine recovers itself, thus 
enabling the amount of work thrown off to be determined. The work is 
then again applied, and the reverse effect observed and recorded. Complete 
tests should comprise a variation of steam pressures, loads and other con- 
ditions, as well as dynamometrical measurement of the actual power 
developed." 

It not infrequently occurs after an ordinary throttling engine has been 
used a few years, that the speed becomes variable to such a degree that it 
interferes with the proper running of the machinery. This occurrence can 
generally be traced directly to the governor. When it does occur, the gov- 
ernor should be taken apart and thoroughly examined ; if the needed 
repairs are such as can easily be made in an ordinary repair shop, they should 
be made at once, if not, a new governor should be purchased. The price of 
governors is now so low that it is better and more economical to buy a new 
one than lose the time and pay the bills for repairing an old one. The gov 
ernor made by R. W. Gardner, of Quincy, 111., (Fig. 67) may be recommended. 

Gardner's Governor. — This governor is made with or without an 
automatic stop. In Fig. 67, it is represented in its automatic form. The 
valve is novel in construction and method of balancing, and consists of two 
discs connected by guide bars. By the peculiar method of receiving and 
delivering the steam, the valve is passive under varying pressures, and is 
affected by the current action of the steam. 

A committfie of the Franklin Institute made tests of Gardner's Governor 



GO VERNOR. 167 

in 1877 or 1878. Brief extracts from these tests are given below. The 
ordinary pendulum governor must run faster or slower to admit less or more 
steam, hence the engine must run faster or slower for that purpose. This is 
because a higher position or greater divergence of its balls demand a higher 
speed, and vice versa. But it is desirable that engine and governor should 
run at a uniform speed, and that the changing demand upon the engine for 
work be met by a change in the point of cut-off, in the case of an automatic 
cut-off engine, or in the amount of steam admitted, in a throttling engine. 

There is no governor of which we know which is perfectly isochronous 
(or even speeded); but in the Gardner Governor this quality exists in a high 
degree, as shown by the tests made at the Franklin Institute in 1877. The 
pendulum balls are hung to a toggle joint in such manner that a rise of the 
balls, due to an increase of engine speed, tends to flatten the toggle out later- 
ally, and a decrease in speed, or dropping of the balls downward and ' 
inward, tends to open the toggle laterally. Attached to a horizontal lever 
is an adjustable weight which tends to flatten the toggle out horizontally. 




Fig. 67.— Gardner Governor. 

The governor is regulated by setting the weight on the horizontal lever, far- 
ther in or out (or by increasing or diminishing it), and by a screw at the top 
acting on the toggle. 

At the Franklin Institute experiments, with the ball 8-| inches from the 
centre and the toggle screw full up, the maximum revolutions was 216 and 
the minimum 192, the regulation being to 11.8 per cent. With toggle screwed 
down y^^ inch, and weight the same as in the first experiment, the regulator 
was to 12.54 per cent. With the weight 6f inches from the centre, and toggle 
left -^ inch down, the regulation was within 6.9 per cent. With weight 5 
inches from centre, and toggle allowed full action, regulation was to within 
14.55 per cent, of isochronism. 

No steam engine should be without an "automatic stop motion," by 
which the governor shuts off steam entirely, and at once, in case of breakage 
of main belt, or similar accident, which would otherwise cause damage by 
permitting the unloaded engine to "run away." 

Foundation. — The foundation should be solid, massive, well laid in 



168 THE STEAM ENGINE. 

cement, and accurately level, otherwise there is wear and loss by reason of 
vibration and settling. If either main bearing sinks, the shaft will be strained 
and the main journal and brasses heat and wear. Foundations should be 
of brick or cut stone, upon a solid concrete bed. The bolts should be stout 
and run well down through. 

The bed-plate should be leveled up with sulphur, lead, or Portland 
cement. 

Steam Cylinders. — Cast iron is the metal generally employed for 
steam cylinders. The hardest iron that it is possible to work should be used 
for this purpose. Steel bushes have been used, and have well repaid in dura- 
bility the extra cost. In order to make the bore perfectly true, large cylinders 
should be bored in the position they are to occupy when they are in use. 
The cylinder should be sufficiently thick to provide for boring and reboring, 
and to give perfect stiffness of position and form. With some forms of cut-off 
the admission of steam to the cylinder partakes of the nature of an explosion, 
hence the cylinder needs to be extra strong. The thickness should increase 
with the boiler pressure and with the diameter. The cylinder should be thick 
enough to stand the required steam pressure and to allow for reboring two or 
three times. The heads may be strengthened by external ribs. For average 
practice the heads may be 1:1^ times the thickness of the walls. Thorough- 
fare bolts are better than studs fitting rust-tight and breaking off. Bolts 
should be close together to prevent leakage. The number of bolts or their 
area should be determined by the boiler pressure and cylinder diameter. 

Care should be taken to get an engine of the proper size and kind for the 
kinds of work to be done. In any case, it is best to have high initial steam 
pressure and high grade of expansion. This is simply as a matter of economy. 
The passage from the ports to the cylinder should be as straight and 
smooth as possible. To get a cylinder with the least surface compared 
with its volume, the diameter of the cylinder must be equal to its length. 
For this reason, the best relative proportions between piston stroke and 
diameter are obtained when they are equal. Then use of short cylinders 
has the advantage of reducing the piston speed, and, consequently, the wear 
on the piston packing for any given number of revolutions, although the 
steam cylinder wears the sarne for any given number of strokes per minute. 

Fly-Wlieel. — The fly-wheel \vill not control the speed of the engine 
for any length of time, nor will it render the motion of any engine exactly 
uniform for even a short period of time ; but, if it is properly proportioned 
in weight, diameter and speed, to the power exerted by the steam cylinder, 
it will confine the variation of the engine during any one stroke within 
reasonable limits. The function of the wheel being to store up work to be 
given out when required, the larger it is and the higher its speed, the more 
steadily it runs, and only for high cost and increase of friction, it would be 
impossible to make a fly-wheel too large. The more irregular the work the 
heavier the fly-wheel should be. If there is any one point where the motion 
is particularly variable, the conditions may be improved by introducing a 
fly-wheel at this point. The fly-wheel generally has a diameter from three 
to ten times the length of the stroke. Of course, the same amount of work 



STEAM CYLINDERS—FLY WHEEL, ETC. 169 

can be got out of a lighter weight of metal if the rim is made large enough. 
The weight and cost of a fly-wheel may be diminished by increasing the 
number of strokes or the diameter of the wheel. Watt's rule is to make the 
work stored in the fly-wheel equal to the work of the engine during seven 
and^ half strokes. Bourne's rule makes the work stored in the fly-wheel 
equal to that developed by the steam cylinder in six strokes. There are 
some machines which will permit of more uneven motions than others, as 
for hammer work. Pumps and shearing machines will permit rather less 
irregularity. Flour mills require an approximation to a uniform speed. 
Weaving machines and paper mills require still greater uniformity. Cotton 
spinning machines must have a very uniform speed, and spinning machinery 
for very high yarn numbers is the most exacting of all. 

The centre of gravity of a fly-wheel must coincide with the centre of the 
shaft on which it is placed. A fly-wheel may be circular and yet have its 
centre of gravity outside that of the shaft. It may be out of circle and yet 
have its centre of gravity coincide perfectly with that of the shaft. In this 
latter case it might serve excellently well as a regulator, but would not do as 
a pulley fly-wheel, because if one of its diameters was longer than another it 
would impart uneven motion to all smaller wheels driven from it, and the 
smaller these wheels the greater the disproportion would be. There is a 
certain limit beyond which the rim of a fly-wheel cannot be speeded, because 
there is a certain point at which there is danger of bursting the rim by centri- 
fugal force. Eighty feet per second rim speed should not be exceeded. 

Stroke. — When the stroke and cylinder diameter are equal there is 
less surface for condensation, less piston speed for a given rotation speed 
than where the stroke is longer, and less wear on the packing ; although for 
a given number of rotations, the cylinder wear is the same for any given 
number of strokes per minute. 

Steam Chest. — The steam chest, where there is one, should be as 
small as possible to lessen loss by condensation. The thickness of steam 
chest is determined by reference to the breadth and longest inside measure- 
ment, the boiler pressure and the tensile strength of the iron forming it. 

Area of Steam Ports. — The area of steam ports is governed by the 
piston speed. The greater the piston speed the greater the required port 
area. For 600 feet per minute piston speed, the port area may be -^^ the 
piston area, and in this proportion for other piston speeds. 

Piston Head. — Horizontal cylinders take broader and thicker piston 
heads than vertical cylinders do, and the higher the speed and rougher the 
usage, the greater the piston thickness needed. The thickness also should 
vary with the diameter of the cylinder. 

Piston Rod. — The piston rod should be of steel, as giving with the 
same diameter greater smoothness and stiffness than a wrought-iron rod, 
or for the same stiffness less weight and less reduction in the area of the 
crank side of the piston, which is always less than the other side. The rod 
must stand the alternate pull of the heaviest work and not bend in the 
slightest degree, else the packing will be destroyed and work lost. 

Slides. — When an engine throws over while the piston head moves 



f 



170 THE STEAM ENGINE. 

toward the main shaft, all of the pressure and wear come upon the lower 
side ; and vice versa. It is best that the engine should throw over, as lubri- 
cants spread over the lower guide better than on the upper, and because 
overthrowing tends to press the guides down to the beds rather than to 
uproot them. 

Cross Head. — The cross head is generally laid down by rule of thumb. 
When an engine throws over all the wear and pressure come upon the under 
slide and when it throws under the upper guide gets it. Cross heads having 
only one guide would answer only for engines runninc; in one direction. 
For purposes of lubrication it is better to have the engine throw over; and 
this also enables the guide to be made stiffen Where guides are fastened 
all along their length to the frame they may be of cast iron, but under other 
circumstances they should be of wrought iron or steel, which are more rigid. 
Connecting Rod. — The connecting rod is generally two or four times 
the stroke. The connecting rod diameter should increase with the boiler 
pressure and steam cylinder diameter. A steel connecting rod may be from 
one to one and a half times the diameter of an iron piston rod. 

Crank Pin. — The crank pin must be strong enough not to break, and 
also of such proportion as not to heat; the latter being the most difficult 
thing to accomplish. The less the diameter the easier oils are expelled. 
Brass boxes conduct heat two to four times quicker than cast iron ones. 
Where the pressure exceeds 195 pounds per square inch of projected area, the 
boxes had better be of brass.or soft metal, because if the film of lubricant breaks 
the metal will go, while with cast-iron boxes heating commences and cannot 
well be stopped. Increase in speed increases the crank pin friction more 
than increase of pressure does. This is because the lubricant is expelled 
more rapidly. The length of the crank pin should increase with the co- 
efficient of friction, the boiler pressure, the number of revolutions per minute 
and the diameter of the connecting rod. 

Within reasonable limits, the longer the crank pin the cooler it will work, 
its diameter having little effect upon the heating, because if the diameter is 
increased the pressure per square inch is lessened in just the proportion that 
the velocity of the rubbing surface is increased. 

The crank pin is abeam fixed at one end and loaded uniformally through 
its length, but sometimes by reason of deflection it is more like a beam fixed 
at one end and loaded at the other. 

The length of steel and wrought-iron crank pins is the same, and the 
thickness maybe the same also. Steel makes the best crank pin by reason 
of its greater strength and better surface ; though steel pins have the dis- 
advantage that they are liable to snap when not working truly. Where the 
initial and the final pressures upon the crank pins are equal the reciprocating 
parts should be as light as possible. AVhere an engine cuts off at half stroke 
the pressure is greatest at mid-stroke. 

Crank. — The crank should be of wrought iron or steel. Cast cranks 
will not admit of the pin being shrunk in the eye without danger of cracking. 
High heat in shrinking is apt to warp a forged crank. It is, perhaps, better 
to give a little taper to the pin and use hydraulic pressure to force it in. 



CRANK— PACKING, ETC. 171 

The tapering faces of the crank ought really to be a parabola having its base 
in the centre of the shaft and its vertex in the centre of the crank pin. The 
nearest outline to this would be its tangents. 

The use of two or more keys is attended with great economy of material in 
the keys and lessens reduction of cross section of the shaft, while the safety 
is equally great. 

Piston-Head Packing. — A packing ring larger than the cylinder will 
never fit the cylinder when cut to pieces. The safe side of a piston fit is the 
small side. Even those rings which are intended to spring out of their own 
accord and fill the cylinder, should be turned to fit, and after they are cut 
they may be opened out by pening or by expanding them on a lathe chuck. 
An engine should not be packed tight in any part. If it cannot be kept in 
good order without squeezing the packing down hard, it must be in poor 
condition. A cylinder that is scratched, or is worn to a shoulder on the ends, 
can never be made tight. 

Piston-Rod Packing. — The packing of the piston rod and valve rod 
is very frequently out of order. The causes of this are too high speed, want 
of alignment, leaky piston, bad piston rod, too high steam pressure, too little 
cylinder clearance, character of the packing, manner of applying it, and kind 
of treatment it gets. If the engine is out of line the piston will crowd the 
packing to one side at certain points of the stroke. If the rod is badly fluted 
the steam will escape through the grooves; If the piston leaks there will 
be too much cushion, which will cause the packing to leak. If there is too 
little clearance between the follower and the cylinder head, the steam will 
escape through the stuffing box. If the packing rings are cut too long they 
will not hug the rod; if made too short they will not meet, and in either case 
there will be leakage. If the material is not the proper size of the box, no 
amount of screwing up will make it a tight job. If the gland is screwed up 
too tight at first, the packing will be destroyed, as will be the case with too 
high engine speed. High pressure, with its attendant high speed, ruins most 
packing. Few engines have deep enough stuffing boxes ; there should be 
enough room for four rings at least. For packing purposes there are a great 
many materials, such as soapstone, paper, india-rubber, asbestos, tin-foil, 
webbing, wire cloth, metal rings, etc. To properly pack the box, put just 
as much packing in it as will barely allow the gland to enter, screw it up 
solid and put it in place, then slack it up to allow for expansion when heated. 
If there is too much leakage, stop the engine, take out the gland, remove a 
few pieces of packing and replace them in another position which may stop 
the leak. Never set the packing, when taken out, on the floor, or in any 
place where dirt or grit may adhere to it ; keep it tightly wrapped up. Never 
use rough instruments to remove the packing, as you may scratch the rods. 
To find the diameter of packing for any stuffing box, measure the diameters 
of the rod and of the gland, and half their difference will be their proper size. 
One of the best metal packings is that made by L. Katzenstein, of New York. 
It consists of coned split rings of anti-friction metal, which surround the 
rod and make it smooth and burnished (Fig. 68). The metal composition 
employed for this packing adheres to the rod, and at the same time is soft 

12 



172 



THE STEAM ENGINE. 



enough not to affect it. The construction is composed of conical plates 
and different rings, those again composed of two parts. The exterior cone 
presses the interior against the wall of the stuffing box, and even under 
great pressure it remains locked. As each ring is a valve seat in itself, 
and each is divided into two parts, the whole is elastic and works easily. 
In this series of half rings (each section being composed of four pieces) 




the corresponding pieces in all the sections are exactly alike, so that any 
piece broken, injured or worn can be easily replaced. These sections, 
also, are so placed as to have intermediate annular recesses, within which 
the water of condensation may be collected, and which, moreover, will 
permit the entire packing to be taken apart for purposes of inspection, 
or reset from time to time in case of wear. Next to the gland a gasket of 
soft packing is laid, capping the metal packing and enhancing the elas- 



CARE OF A STEAM ENGINE. 173 

ticity. The advantages claimed for this metal packing are the following : It 
gives a perfectly tight stuffing box, likewise a steadying to the rods and 
stems, with little or no friction ; it keeps the rods and stems perfectly 
smooth, and requires little lubrication ; it will not corrode the rod when the 
engine is not in use. 

The rubber-core coil packing, made by the New York Belting and Pack- 
ing Company, is largely used and gives good satisfaction. 

In about two engines in three, if we glance in the neighborhood of the 
stuffing box, we shall see one or more jets of steam issuing from around the 
rod during the whole or during a portion of every out-board stroke, or if we 
do not see this we will find the rod to be packed down so hard that it is 
gradually becoming worn or fluted. The piston-rod packing must let the rod 
move freely in every direction, with little friction, and without allowing the 
steam to escape. It must also be durable. With hemp or tow packing the 
rod becomes dull and appears scratchy as though draw-filed with a cross file. 
This is by reason of the grit which the fibres contain. Then the scratched 
rod cuts the packing. This is more likely to be the case if the rod is out of 
centre, varies in diameter, is crooked or out of round. Piston rods wear 
smallest in the middle, and oval at the ends, the lower end of the rod being 
worn most upon the bottom, while the crank end will be most worn on the 
top. Very often the rod and piston are purposely set a little high at first. 

Care of a Steam Engine. — Whenever it is necessary to make repairs, 
the work should be done at once. Oftentimes a single day's delay will increase 
the extent and cost four-fold. If an engine is properly designed and built, 
the repairs required ought to be very trivial for the first few years it is run, 
if it has had proper care. It may be said in reply to this, " True, but acci- 
dents will happen in spite of every care and precaution." That accidents do 
occur is true enough, that they occur in spite of every care and precaution is 
not true. In almost every case accidents may be traced directly back to 
either a want of care, negligence or to a mistake. Eccentric straps are likely 
to need repairs as soon as anything about an engine. They should be care- 
fully watched at all times. If they are likely to run hot, it is also probable 
that there is more or less abrasion or cutting going on. If so, and prompt 
measures are not taken to arrest it, they are likely to cut fast to the eccentric 
and a breakage is sure to occur. When the straps begin to heat, the bolts 
should be slackened a little, and at night, or perhaps at noon, the straps 
should be taken off and all cuttings carefully removed with a scraper (not 
with a file), the rough surfaces on the eccentric being removed in the same 
manner. The straps should be run loose for a few days, gradually tightening 
as a good wearing surface is obtained. The main bearing, if neglected, is a 
very troublesome journal to keep in order. The repairs generally needed are 
those which attend overheating and cutting. The shaft, whenever possible, 
should be lifted out of the bearing, and both the shaft, bottom of main bear- 
ing and side boxes carefully scraped and made perfectly smooth. It some- 
times occurs that small beads of metal project above the surface of the shaft, 
which are often so hard that neither a scraper nor file will remove them, 
Chipping is then resorted to, and the fitting completed with a file and fine 



174 THE STEAM ENGINE. 

emery cloth. In the care and management of automatic engines it is difficult 
to say just what particular attention they need, owing to the variety of styles 
and the peculiarities of each. As a rule, however, they require,^ first, to be 
kept well oiled ; second, to be kept clean ; third, to be kept well packed ; and, 
fourth, to be let alone nights and Sundays. There is little doubt that there 
has been more direct loss resulting from a ceaseless tinkering with an engine 
than results from the legitimate wear and tear to which the engine is sub- 
jected. The writer does not wish to be understood as saying that builders 
of this class of engines are infallible ; it might be difficult to prove any such 
assertion in case it was made, but it may be said, with truth, that the engines 
of this class now in the market are carefully designed, well proportioned, of 
good materials and workmanship, and, as examples of mechanism, are en- 
titled to take very high rank. A manufacturer writes thus, to the builder of 
his engine : "The engine which you furnished us (i6 x 30) has been in con- 
stant use for more than four years, running at 132 revolutions per minute, 
sometimes as auxiliary to water-power and sometimes at its full power. It 
has cost us nothing for repairs." It is essential to the economical working 
of these engines that the cut-off mechanism be in good order and properly 
adjusted. Whenever the valves need resetting the final adjustments should 
be made with a load on the engine, and with the indicator attached to the 
cylinder, the valves being set by the card rather than by the eye. No gen- 
eral rule can be given for setting the valves, as the practice varies with the 
size and speed of the engine, nor is any rule needed, for the indicator will 
furnish all the data required. The adjustments may then be made so as to 
secure prompt admission, sharp cut-off, prompt release and the proper com- 
pression. 

The practice of fitting a slide valve to its seat by grinding both together 
with oil and emery is wrong, and should never be resorted to. The proper . 
way to fit the surfaces is by scraping; this insures a more accurate bearing to 
begin with, and will also be entirely free from the fine grains of emery which 
find their way and become imbedded in the pores of the casting, and are 
thus liable to cut the valve face and destroy its accuracy. The scraping of 
the valve and seat has a beneficial effect by causing the removal of the fine par- 
ticles of iron which are loosened by the action of the cutting tool in the plan- 
ing machine, and which ought to be fully removed before the engine leaves 
the manufacturer's hands. Aside from this, it is doubtful whether the scrap- 
ing amounts to anything practically, for the reason that the cylinder and valve 
are fitted cold and their relative positions are distorted by the action of the 
heat of the steam, once the engine is in use. The scraping, which simply 
renders the valve face and seat smooth and hard, is all that is sufficient to 
begin with, and may be rescraped after the valve has been in use a few days, 
should it be found necessary, which will not often be the case in small and 
ordinary sized engines. 

Although large slide valves are still used in marine engines, it is only 
because no equally efficient substitute has been brought out. They do not 
work satisfactorily for any length of time, especially at high speed. The 
slide valve cannot cut off at less than half stroke very well without interfering 



POUNDING— CYLINDER LUBRICATION. 175 

with the exhaust. The horizontal engine has the advantage of being compact, 
easily held to its foundation and accessible. To illustrate the difference be- 
tween a large engine at slow speed and a small one at high speed, a i6 x 48 inch 
engine, using eighty pounds of steam, cutting off at one-fourth and running at 
sixty revolutions, may be replaced by an engine of the same pressure and 
same cut-off, having a 13 x 24 cylinder and running at 200. For small 
powers and small investments the engine had best have a common slide valve 
if the cylinder is eight inches or less in diameter. From eight to fourteen 
inches diameter the automatic slide cut-off answers well, as being low-priced, 
economical and efficient, running at a quick speed and giving as good results 
as a large and more costly slow running machine. In most engines there is 
more trouble with the crank pin than with all other parts. The crank pin is 
very liable to get hot, and is very troublesome when it does get so. There 
are several reasons for this heating, among which may be mentioned that the 
main shaft is not square with the engine, the pin not properly fitted to the 
crank, and too small, or the boxes too tightly keyed or not well enough oiled. 
The old style of oil cup is very poorly adapted to crank pin lubrication, and 
should be superseded by some of the new inventions for this purpose, which 
are automatic, effectual and certain in their action. 

Pounding. — Lack of alignment causes knocking and pounding. With 
the Corliss type of frame, if the engine is properly aligned at first, it will not 
be likely to get out of line except that the wear of the crank shaft bearing 
will cause the shaft to drop. The crank centre line must stand true with 
the axle line of the cylinder when the crank is on the dead centre. If the 
engine has a flat bed and adjustable guides, any error in the planing of the 
cylinder flange is magnified five times at the pall block, hence the cylinder 
must be so lined that the line through its axis will pass through the pillow 
block at the centre of the bore of its brass. It must not be expected that a 
new engine will always start off right without any trouble. Bearings will 
bind, joints will leak, etc., and it takes a little time for everything to get to 
working nicely. 

Joshua Rose says that an efficient method of locating a "pound " in a 
steam engine is to place one end of a piece of quarter-inch wire, about eight 
inches long, between the teeth, applying the other end to each end of the 
crank shaft, bearings, cylinders, &c., the violence of the shock in the vicinity 
of the pound being sufficiently the greatest to indicate its whereabouts. Mr. 
Rose remarks that all the mysterious "pounds" that annoy the engineer may 
be traced to a want of truth in the crank pin, or a want of being in line of 
the main parts of the engine, usually the cylinder and main shaft. 

Cylinder LiUbrication. — There is much trouble caused in connec- 
tion with cylinder lubrication. In some cases the lubrication is spasmodic, 
in others it is too limited, and in others there is too much oil fed in. There 
are cases where animal oil is used in such quantities as to cause many troubles 
in the boiler, to which the exhaust steam is returned by some kinds of heat- 
ers. When mineral oil is used this trouble does not occur ; but excessive 
lubrication with mineral oils is apt to cause leaks, which more than counter- 
balance the advantages of the scale-removing properties of mineral oils. 



176 



THE STEAM ENGINE. 



There should be used for cylinder oiling the best grades of mineral oils, 
having a slight proportion of purest animal oil ; in which case it is best that 
the oil be introduced in the steam, drop by drop. By the ordinary way 
of introducing it into the steam chest direct, it is found that some por- 
tions receive more oil than others, and there is a waste of oil. The lubrica- 
tor shown in Fig. 69 (made by the Detroit Lubricator Manufacturing Co.), 
meets all of these requirements. It is described as follows : A, oil reservoir ; 
B, steam pipe ; C, oil filler ; D is a water-feed valve ; E, the valve to 
regulate the flow of oil ; F F, a steam tube and condensing chamber ; G, a 
valve to draw off water to prevent freezing; H, the visible feed-water 
chamber ; J, a glass indicator ; K, the oil discharge pipe ; M, the governor 
valve ; N, a valve to correct unsteadiness in the feed ; O, vent. 

The steam pipe is tapped with a one-half or three-quarter inch gas tap, to 
receive the oil discharge pipe. Then it is tapped three feet or more above 
the cock of the condensing chamber, using one-quarter inch pipe for steam 
connecting tube, which is to be attached to the top of the condenser, placing 
a globe valve between the steam pipe and the condensing pipe. To fill the 
cup the valves D and E should be closed. The valve G open and the water 
drawn off ; then the valve G closed and the cup filled with oil. Then open 
the valve D, then regulate the flow of oil with the valve E. With this lubri- 




FiG. 69. — Sectional View of Lubricating Oil Cup. 



cator the flow is rendered regular, and can be seen passing drop by drop 
through the transparent water chamber, and it is claimed that it can be regu- 
lated to feed only one drop per minute when required. 

Graphite in Steam Cylinders. — " Having heard of the application 
of dry plumbago with success, it was concluded to give it a trial. The 
engine upon which the experiment was carried on was an 11 x 30 horizontal 
engine, piston speed, three hundred feet per minute, and was known as the 
"West Poppet Valve Automatic Engine." It was worked up to its full 
capacity, and, to insure a fair trial, the existing oil cup was exchanged for a 
goblet-shaped tallow cup with a lid, after which the piston follower and 
springs were taken out and cleaned. When ready to start the engine, one- 
third of an ounce of finely powdered Ceylon plumbago was placed in the cup. 
As soon as the engine was fairly under way, the valve of the grease cup was 



GRAPHITE— INDICATOR DIAGRAMS, ETC. 177 

opened half way ; after running some time it was opened all the way. When 
the engine was stopped at noon, on examination of the grease cup, the 
plumbago had all passed into the cylinder, of which there had been strong 
evidence soon after starting, as the piston rod became coated with it. Upon 
starting up in the afternoon, one-third of an ounce more was placed in the 
cup, and the engine run until six o'clock, with a similar result. There was 
no noise in the cylinder, either in the starting, running or stopping of 
the engine ; and after eighteen months' use, with the above named 
quantity applied twice a day, no noise has been heard in the cylinder, 
except when the steam was shut off for the purpose of stopping the engine, 
when it would be heard during one or two strokes of the piston, just 
before the engine stopped. This occurred not oftener than would have 
taken place if tallow or oil had been used. Soon after beginning its use ^ 
portion of the plumbago would be found remaining in the cup ; to obviate 
this, about an ounce of water was poured into the cup after the plumbago 
had been put in, when a decided improvement was observed — so much so, 
that it can now be fed into the cylinder as readily as oil or tallow. After 
four weeks' use, the cylinder-head was taken off, and the working part of the 
cylinder was found coated with plumbago, which could not be easily rubbed 
off with the fingers ; the interior of the piston was found as clean as when 
it left the lathe, so far as dirt of any kind was concerned, and such is the 
condition to this day." — Cor. Amertca?i Machinist. 

Indicator Diagrams and Expert Tests. — The indicator shows 
the performance, condition, power and economy of the steam engine ; the 
power wasted by want of lubrication, improper alignment of shafting, badly 
designed gearing, slip, or excessive tightening of belts. It can be used to 
register the amount of power consumed by each tenant or machine ; detects 
carelessness or incapacity of the engine runner ; points out leaks, chokes, 
bad packing, condensation, uneven or badly-timed valve motion, etc. The 
indicator diagram shows the pressure in the cylinder at every point of the 
stroke, points of cut-off, release and exhaust closure, the loss between the 
pressures in the boiler and cylinder and condenser, the power developed in 
the cylinder. When the weight of steam delivered to the cylinder is known 
it can show the percentage of steam accounted for up to the release. It is 
not safe to estimate the economy of performance entirely from the indicator 
diagram, because leaks into or out of the cylinder cannot be thus measured, 
and when the engine leaks the diagram will show too high a duty. It 
generally pays to have the engine and boiler overhauled by an expert, and 
certain portions altered or renewed. In one case known to the writer a 
change of the cylinder saved one third of the fuel. " The Prony Brake," or 
friction brake, and the dynamometer, measure with sufficient accuracy the 
power developed by a motor, and are valuable to check the indicator. 
Engines rated by their builders at loo H.-P., with 22-^ pounds of steam 
per hour per H.-P., are sometimes found by indicator or brake to develop 
but 75 H.-P., consuming 30 pounds of steam hourly. In each case 2,250 
pounds of steam is used, and probably 250 pounds of coal burned ; but 
in the second instance both power and economy are too low, and might 



178 



THE STEAM ENGINE. 



sometimes be brought to proper capacity and duty simply by resetting 
the valves. Engines having irregular motion, causing great loss in cotton 
factories, paper and flour mills, etc., can always be brought to proper 
performance by intelligent treatment, after using the indicator to reveal 



f 









\ 



the cause. Regularity is especially important to those using the electric 
light. Non-condensing engines that are wasteful by reason of back 
pressure, may at times be made economical by the application of an 
ejector condenser. The technical papers are constantly receiving such 



WHEE'LOCK ENGINE. 179 

communications as the following : " I have recently taken charge here as 
superintendent, and I find the engine not working well. It appears to draw 
more steam at the head end of the cylinder than at the crank end. It works 
with a struggling, jarring sound, and certainly is using more steam than the 
amount of machinery warrants. I am seeking for the diagnosis, so as to 
apply the proper remedy. Will some of your correspondents throw in a 
little help ?" The expert can help such cases by straightening out the 
faults in the engine, and seeing that the superintendent gets a competent 
man to run the engine. 

Wheelock Engine.— In the Wheelock Engine, Figs. 71, 72, 73, 74, 75, 
76 and 77, the principal peculiarity is the valves, all of which are on the lower 
side of the cylinder, instead of there being two admission valves above 
and two exhaust valves below, as is the case with the various Corliss types. 
There is at each end one main valve performing the functions of an ordinary 
slide-valve without the friction of the latter. This main valve allows steam 
admission and exhaust. Upon the back of each main valve there is a cut-off 
valve, having a cavity in its face allowing double admission and consequent 
rapid closing. The cut-off valves are well opened before the main valves 
are ready to open their induction ports. This is an advantage, especially 
where steam follows but a short portion of the stroke ; for if the 
cut-off is open but a crack, as in cases where the lead is controlled by the 
cut-off, the mechanism is frequently not sufficient to close it, and steam 
sizzles through the entire stroke, thereby causing irregularity of motion. 
The valves are somewhat conical, so that any wear in diameter may be taken 
up by slight end adjustment. They are hung upon ordinary steel trunnions 
in hardened steel bushings, so that they do not really touch their seats but 
are held in steam-tight contact without friction and wear. The steam pres- 
sure keeps the collar of the valve stem in contact with the bushings, forming 
a joint with the steel valve stem or trunnion, thus doing away with the neces- 
sity of a stuffing box. This arrangement of valve reduces the clearance to a 
minimum, and also, as before stated, guards against a waste of steam through 
the exhaust port, if there should be any leakage pass the cut-off valve. The 
work of removing the cut-off valves is not performed by the governor, but 
that important feature simply indicates the point at which the "crab claw" 
liberates the cut-off. The cut-off is worked from the cramp of the main valve, 
the connection to the latch link being made by an eccentric bolt, making ad- 
justment very handy and producing the benefits of the celebrated " wrist " 
motion, without its usual complications. The steam chest is underneath and 
cast in one with the cylinder, as is also the exhaust passage. The latter 
is entirely separated from the steam chest, and, while in no way influencing 
the live steam, should easily dispose of any accumulation of water. The 
cylinder has only one port at each end, and the valves being suspended should 
not gouge out the seats, nor do the latter need to be reset. The object of 
this construction is to get the effect of steam balancing, without the objec- 
tions that apply to that method. The steel stems have been found in practice 
to wear endwise in about equal ratio with the surface of the valves and their 



180 



THE STEAM ENGINE. 



seats, and as the valves are suspended with the surfaces in slight contact, while 
the pressure causes the valves to tend to their seats, durability is obtained. 




The new form of throttle valve, Fig. 73, has points of advantage— that the steam 
is always on that side which will press the valve to its seat. The stem has a 



WHEE'LOCK ENGINE. 



181 



collar in contact with the inner shoulder of the bonnet, doing away with the 
stuffing box. As the screw is made to push the valve from its seat, it forces 
the collar against the shoulder, and makes a tight joint and swivel valve, 
without rattling when partly shut, the pressure on both the valve and the 




'Stem being always toward the atmosphere. The other details of the engine 
embody many tested novelties, resulting from a knowledge of the wants of 
the simple, durable and easily managed cut-off engine. The piston packing, 
shown in Fig. 75, is well known in this country, being used by other engine 



182 



THE STEAM ENGINE. 



builders desirous of having a steam-tight packing that will not cut out the 
cylinder bore. 




FiG. 74. — Piston Head. 



KiG. 75. — Packing Rings. 




Fig. 76.— Section of Piston Head. 



—A: 




Fig. 77. — Main Valve, Trunnions, &c. 



Computation of Horse-Power, — A very neat little formula, easily 
remembered, for computing the- horse-power of a steam engine, is that given 



ERRATA. 

Page 183. — Line five, for " group," read ''''crank." 

Line thirty-eight, for "the effective steam pressure," read "the mean 
effective," etc. 

Line forty-two, for " space," read " stroke ; " for " L," read "/." 

Page 184. — Line twenty-four, for ''^ plus the clearance," read ''^ less the 
clearance." 

Formula, line thirty-one, should read, /= ^ — ^^ °^' — ^^ 

Line thirty-two, for " mean or average pressure," read " mean or average 
effective pressure." 

Page 185. — Line thirteen, for " reputation," read " regulation." 



CO MP UTA TION OF HORSE-PO WER. 183 

by Prof. W. D. Marks, of the University of Pennsylvania. The rule, of course, 
refers only to indicated horse-power. Let P represent the mean pressure of 
steam on the piston head per square inch, in pounds, L the length of stroke 
in feet, A the area of the piston head in square inches, and N the number 
of strokes (/. e., twice the number of revolutions of the group) per minute ; 
then (HP) the horse-power, will be equal to 



33,000 

This formula is sensible, because the letters spell a familiar word. Those 
formulas which give a lot of Greek letters bother the average mechanic. It 
must be remembered that it will not do to be wild in assuming the unit of 
measurement, as the formula would cipher out different things with feet 
from the answer with inches. From this very simple formula may be found 
any one of the five elements if the other four are given. In this we have 
PLAN given to find horse-power ; but we may take advantage of the same 
relations to find any one of the others. Thus, if we have given the horse- 
power required, and know the length of stroke of our engine, its diameter or 
area of piston, and the number of strokes necessary for the engine to run 
in order to give certain machines in the mill a certain speed, we may find the 
pressure needed to get this horse-power by the formula P = ^^ (HP) ; 
from the same figures the length of stroke is equal to ^^ (HP) ; the 
area equal to ^^'°^ln — ' ^"^ having given the steam pressure, the length 
of stroke and the piston diameter or area, we can find the number of strokes 
needed to get a given horse-power by ^^'°^l^ — ■ In such formula it is the 
custom not to write the sign of multiplication, it being understood that two 
letters written together, as A B in a formula, are to be multiplied together 
Thus, PLAN means P times L times A times N. To avoid confusion, the 
letters H P are written either as one character, which can be done only in 
manuscript or by having special types to make this character, or they are 
written with the parenthesis, ( ), to signify that they denote only one quantity. 
There are other considerations, such as clearance (or waste space in cylinder 
and in steam passages), throttling or wire-drawing (reduction of pressure in 
cylinder, by small and tortuous passages), back pressure, &c., which modify 
the above figures. 

"Factor of horse-power" is a conventional term not much used in the 
East, and means the product of area and speed of the steam piston, divided 
by 33,000. Thus, when the area of piston is expressed in square inches, and 
its speed in feet per minute, the so-called " factor of horse-power" multiplied 
by the effective steam pressure per square inch, gives the horse-power of the 
engine. The effective steam pressure, means the mean pressure above the 
vacuum in the condenser, or in a condensing engine above the mean back 
pressure in the cylinder, in a non-condensing engine. 

Following are more detailed formulas for wok of steam: Let L^ length 
of space in feet ; L, period of admission, or cut-off, in feet, not counting 
clearance ; c, total clearance volume at one end of the cylinder in feet of 
stroke ; L', length of stroke, plus clearance in feet; I', period of admission 
plus clearance in feet; R, nominal rate of expansion ; R', actual expansion 
rate ; A, piston area in square inches ; P, total admission pressure in lbs. abs. per 



184 THE STEAM ENGINE. 

square inch (supposed uniform during admission) ; /, average total pressure 
in pounds per square inch, during the whole stroke ; p,, average back pressure, 
in lbs. abs. per square inch, during whole stroke, w, whole work done in one 
single stroke, in foot pounds ; w, work of back pressure for one single stroke 
m foot pounds; W, net work done in one single stroke, m foot pounds. 

To find net work done by steam in the cylinder, for one single stroke of 
the piston, with a given cut-off : First, find in the table the hyperbolic 
logarithm of the actual expansion rate (allowing for clearance) ; add one. 
Multiply the sum by the period of admission plus the clearance, in feet. 
From the product take the clearance (\nfeet). Multiply the remainder by 
the total admission pressure in lbs. abs. per square inch. This gives total 
work on the piston in foot pounds per square inch. Second, multiply the 
average back pressure in lbs. abs. per square inch, by length of stroke in feet, 
This gives loss by back pressure, in foot pounds per square inch. Third, 
take the back pressure from the total work ; this gives net work in foot 
pounds per square inch on the piston. Fourth, multiply piston area in 
square inches by net work per square inch, to get net work in foot pounds 
done in the cylinder, for one single stroke or one-half revolution. 

To find what initial pressure is requisite to produce a given average 
pressure per square inch, for an actual (not nominal) expansion rate, divide 
the product of the average total pressure in lbs. abs. per square inch, for the 
whole stroke, by the stroke in feet ; and divide the product by one, plus the 
hyperbolic logarithm of the actual expansion rate, times the period of 
admission, plus the clearance in feet ; the clearance being taken from the pro- 
duct before using it as a divisor. Written as a formula P = /> (i .j, hyp log ro— ^ ' 
To get the average total pressure in the cylinder, in terms of the initial 
pressure, for a given actual expansion rate : divide the stroke in feet into the 
difference between the clearance in feet, and the period of admission plus 
clearance, times one plus the hyperbolic logarithm of the actual expansion 
rate ; and multiply the quotient by the total initial pressure in pounds per 

square inch. As a formula p = — ^l °^ — ''~^' 

To find the mean or average pressure, take the average back pressure 
from the average total pressure. 

To find the admission period requisite for a given actual expansion rate, 
divide the length of stroke plus clearance, by the actual expansion rate, and 
deduct the clearance from the quotient. 

Power and " Duty. " — The power of an engine means how much work 
it will do, irrespective of how much coal it takes to do this work ; the duty 
is the amount of work it can do with a given amount of steam. 

The theoretically perfect steam engine ought to yield us, for every pound 
of coal burned, 5-^ horse-power. By comparing these conclusions with the 
results of practice, we will see how far from perfection our steam motors 
really are. The actual consumption of fuel per hour per horse-power will, 
of course, vary largely in practice, according as the apparatus is well or 
badly constructed, and properly or wastefuUy operated. But, putting such 
disturbing elements aside, we will take the best results of the best practice in 



POWER AND DUTY— COST. 185 

making a comparison. Taking marine engine practice, which gives us the 
best results, the best of these require from 24- to 3 pounds of coal to develop 
a horse-power. As one-fifth of a pound of coal should develop this mechan- 
ical effect, if all of its heating effects were realized, it is evident that our 
best steam engines are only realizing 1-54-2-5-^2.50, or, say, about one- 
twelfth, or about 8 per cent, of what theory shows us should be realized. 

In buying an engine, have its duty guaranteed in pounds of dry steam per 
hour per horse-power, not in pounds of fuel ; as in the first case the engine 
alone determines the stated economy, and in the second, the boiler perform- 
ance is included ; varying with the kind and condition of boiler, manner of 
setting, covering and firing, quality of fuel, draught, temperature and kind of 
feed-water, etc., etc. Its rating should be guaranteed under some stated 
pressure, point of cut-off, and variation of load ; and its " repilation " should 
be guaranteed under certain conditions of variations of load and of boiler 
pressure. For instance, in a 350-barrel mill, having 80 to 85 pounds boiler 
pressure, and average load 150 to 175 horse-power, with occasional demand 
for 200 horse-power ; in buying a non-condensing automatic cut-off engine, 
it ought to be guaranteed at 24.5 pounds of water per hour per horse-power, 
under one-fifth cut-off, giving 35.2 pounds mean effective pressure, and speed 
not to vary over two per cent. 

The economy rate may be found by dividing 859,375 by the volume of steam 
at the determined pressure, and by mean effective pressure. 859,375 is the 
number of pounds of water an engine would use to develop one horse-power, 
if run by water at one pound pressure per square inch. With higher pressure 
the requisite rate of water would be less ; and with steam the amount would 
be as much less as the volume of the steam at the pressure «/ w/zzV// it is 
released is greater than that of an equal weight of water. One H.-P. — 
33,000 X 12 = 396,000 inch pounds ; or say 23,760,000 cubic inches of water 
per hour per horse-power, for an engine having 396,000 cubic inches per 
minute piston displacement. One pound of water takes up 27,648 cubic 
inches ; and 23,760,000 divided by 27,648 — 859,375. 

Cost of Putting in Steam Power. — The cost of 50, 100 and 250 
horse-power engines of one of the Corliss types has been estimated by the 
builders at $6,000, $10,000 and 822,500 respectively, all ready to run, 
including building, chimney and foundations. The 50 and 100 horse-power 
would be high pressure and the 250 horse-power condensing. 

Cost of Fuel per Barrel of Flour. — The query is often made : 
"What should be the expense of fuel per barrel of flour?" 

This is a question which cannot be answered "on sight," nor even at leisure 
without fuller details than have yet been placed at our disposal. The expense 
naturally depends on many elements, the principal ones being the capacity 
of the mill, the kind of wheat operated upon, the process and machinery 
employed, grades made, system of transmission, excellence with which this 
system is carried out, thoroughness of lubrication, and last in order of 
naming, but not least in importance, the class of engine which furnishes the 
power, of boiler which supplies the steam, and kind, grade and cost of fuel 
consumed. In flour mills, the question of pounds of coal per barrel of flour 



186 THE STEAM ENGINE. 

depends somewhat upon the engine, but generally more upon the boiler. 
Large mills will use less coal per barrel of flour than small ones ; some wheat 
will take more power than others ; new process takes more than old, high 
grades more than low, old mills more than new, complicated mills more than 
those where the transmission and flow of material are simple. Mills that are 
well attended to take less than those that are allowed to sag and get out 
of order all around ; slide valve engines consume more than those of the 
Corliss type ; automatic cut-off less than with fixed cut-off ; belts less than 
gears. Small mills have not the chances for petty economies, that is, for 
percentage economies, that large ones have. If a mill is run in a neighbor- 
hood where coal or wood is dear ; if the boiler is of an uneconomical 
type, badly set and ignorantly fired ; if the engine is one which wastefully 
consumes the steam supplied it, and is run by an ignorant or careless 
engineer ; if cumbrous gears or slipping belts are employed in transmission, 
the shafts are badly hung or out of line, and bearings short or improperly 
lubricated, the debtor side of the expense account will show a liberal 
entry under head of fuel, and more enterprising firms who look more closely 
to these items, will, other things being equal, be readily able to compete 
in the markets with the mill that wastes fuel. If, however, a firm chooses 
that fuel which is cheapest in its neighborhood — as for instance, if it 
burns sawdust or slabs, or slack, or spent tan, where these can be had 
for next to nothing — if a skilled and careful fireman is employed where 
wood or coal is used, so as, by frequent stoking and stirring the fires, 
to get the most out of the fuel provided, an important prime saving is 
made. If the boiler is of approved type, supplied with pure hot feed, is 
well set and jacketed, and with a stack of proper height and proportions, the 
coal bills should show favorably. If the engine is an automatic cut-off of 
good design and construction, neither too large nor too small for the work 
performed, properly erected on solid foundations, and handled by an intelli- 
gent engineer, who looks to it that no leak, or cutting or undue friction is 
allowed to continue after being discovered, the mill owner may feel easier 
about his coal bill than if his profits were being reduced by such a boiler ex- 
hauster as is found in too many mills. If a geared mill, the cogs should 
mesh with true rolling contact instead of sliding roughly upon each other. 
If belts are used, they should be of proper tautness — neither loosely flapping 
about nor drawn up by huge tighteners until the bearings are crowded ; they 
should have a smooth, even surface, straight flush joints, and run on pulleys 
where faces permit perfect contact and good grip. From this point, the 
question of the quantity and character of machinery employed and process 
chosen is one requiring too much space to discuss properly at the present 
time in these pages. In view of all these considerations, we think that the 
wide range of fuel cost of from three to ten cents per barrel is easily accounted 
for. In a good mill a slide valve engine will make loo barrels of flour in 
twenty-four hours with six cords of wood, with eighty pounds of steam. An 
automatic cut-off engine will do the same work with three cords of wood, 
and only fifty pounds of steam, and give better motion. From four to six 
cords of bass wood should make 200 barrels of flour in twenty-four hours. 



COST OF FUEL PER BARREL OF FLOUR. 187 

From twenty-five up to fifty pounds of coal should make a barrel of flour in 
large mills with good management. In the average mill, one horse-power per 
hour may be said to cost about four pounds of coal. A 300-barrel mill driven 
by steam and consuming 150 horse-power will use about 150 x 4 x 24 = 14,400 
pounds per day, or 4,320,000 pounds per year of 300 working days, being 
about 1,928 gross tons. If, by reason of poor arrangement, poor engines, 
poor boilers, poor transmission, or any or all other causes, there is a waste of 
only ten per cent., this amounts to 192.8 tons of coal per year, worth, as a 
minimum, from $400 to S800 in coal alone. 

Herewith are annexed some figures referring to automatic cut-off engines : 
The Minnetonka Mill Company reports making fifteen or sixteen hundred 
barrels of flour per week from hard wheat by patent process, blowing the 
bran 150 feet, using an inch pipe with valve wide open for heating the wheat, 
and carrying power 150 feet with wire cable, for running a wheat elevator, 
all with less than thirty cords of wood. Where slide valve engines took six 
cords of wood to make 100 barrels of flour in twenty-four hours, carrying 
eighty pounds of steam, an automatic cut-off engine did the work with per- 
fect motion on three cords of wood, carrying only forty or fifty pounds of 
steam. A mill in Manitowoc used, with one engine, four and five-eighths 
cords of dry maple wood, three feet nine inches long, to 100 barrels of flour ; 
an improved engine made loif barrels per 2f cords of wood. A 14 x 35 en- 
gine drives six run of stone, three purifiers, two separators, one cockle 
machine, eleven bolts, one packer, one smutter, and all other necessary mill 
machinery, using only one and a half cords of wood per day of ten or twelve 
hours. In Stillwater, six cords of bass wood make 260 barrels of flour. The 
Minnetonka Mill Company makes 200 barrels of flour with four cords of 
wood. One automatic cut-off engine, of which we know, averages 100 barrels 
of flour for each gross ton of coal, or 22.4 pounds of coal per barrel of flour. 
The larger and lower the grade of the output, the smaller should be the fuel 
cost per barrel of flour. 



^*<^ 



13 



CHAPTER XI. 

TRANSMISSION— SHAFTING. 

Shafting — Turned Shafting — Cold Rolled— Hot Finished — Hollow Shafts — Hangers — Bearings — Torsion 
— Couplings— Friction Clutch— To Line Up Shafting — Keys. 

Shafting. — It is of the greatest importance that the shafting and all 
the members which go to form the transmission in a mill should be of the 
proper material, properly designed, proportioned, put up and cared for. At 
one time the most common material for shafting was cast-iron, but this has 
gone out of use, as being too heavy and weak, and lacking in uniformity of 
nature. Wood was once largely used for large shafts, but is now confined 
to the axles of large vertical water-wheels, &:c. Wrought iron, turned in 
ordinary or in special lathes, is now more used than any other material. One 
curious thing about the turned shafting business is that, with most makers, 
no turned shaft is of the diameter that it professes to be, but takes its name 
from the round wrought-iron bar from which it was turned. It is custom- 
ary to take off just 1-16 inch in this turning operation, hence " 2-|^inch " shaft- 
ing is really but 2 7-16 inches diameter, and so on. 

As to sizes of shafting, Cresson makes the shaft the size, instead of the 
hole of the pulley, or letting the shaft come what it will, so to speak. The 
former method is preferable and proper, because most persons ordering 
shafting have something on hand which they have already bored certain 
machinery to fit, and when they find the shafting below the supposed size 
they are obliged to throw away valuable work, and thus lose both it and the 
time to make new. Some concerns call i 15-16 inch, &c. (shafting sizes), im- 
properly by the U. S. standard sizes, 2 inches, &c., but in G. V. Cresson's 
price list each size is printed as it stands, and is made strictly to this size, 
which prevents endless confusion. There are firms which make standard 
size shafting regularly. Cresson calls all of the regular shafting sizes 
by their real and exact names. We are of the opinion that all firms 
should do this, as there has been great difficulty caused to customers when 
ordering. If a customer calls for \\ inch shafting, for instance, the maker is 
compelled to write him asking whether he means \\ inch exact or i 7-16 
inch, and this causes a delay which is sometimes prejudicial to the interest of 
those who wish to order — especially when they are at a distance. 

Turned Shafting — Is, of course, subject to defects arising from the ma- 
terial from which it is made, as well as from the lack of skill, care or special 
apjiliances in producing it. If the material from which it is turned is not first- 
class, the surface of the shaft will be likely to show specks and flaws indicat- 
ing that the interior is in the same condition, and that the shaft is not strong 
nor homogeneous. It is very rare that shafting is not very nearly perfectly 



TURNED SHAFTING. ■ 189 

round at any one point in its length, but it is sometimes found to be of 
greater diameter at one end or in one place than at another, and more fre- 
quently it will be found that out of ten lengths there will be two or three 
different diameters, all professing to be exactly the same nominal diameter, 
and all intended to be just 1-16 inch scant of that nominal diameter. This 
difference in caliper between two lengths in a line gives rise to serious 
difificulties in coupling the lengths together into one continuous line. 

G. V. Cresson, of Philadelphia, gives us the following figures as the 
results of actual calipering of his turned shafting. The fixtures show very 
good work. These results were not obtained by choosing the best shafting, 
but by taking the ordinary stock just as it ran, and therefore give a fair 
average correctness. This establishment makes nothing but shafting and 

its accessories. 

SHAFT = 2.4375". 

3" from the end = 2.435" \ 

23" " = 2.431" >• Minimum difference = 0.002" 

3' 4" " =2.432") 

4' " =2.433" 

6' 2" " =2.432" J 

g' 6" " = 2.434" \ Maximum difference = o.oo5" 

12' 6" " ^ 2.435" ) 

SHAFT 4 15-16" = 4.9375". 

n" from the end = 4.032" ), J. . ,.~. 

^ ^-^ \ Mmimum difference = o 005 

3' " =4.937' > 

7 4-9J7 ( Maximum difference = 0.006" 

9' " =4.937" ' 

Another shaft of 4 15-16" measured all through 4.932" ; therefore maxi- 
mum difference = 0.005". 

SHAFT I 15-16" = I-9375'- 

12' from the end = 1.934" \ Minimum difference = 0.002" 
3' " = 1.932 ) 

5 1-935 [ Maximum difference = 0.005" 

7' 6" " =1.935") 

SHAFT 1 15-16" = 1.9375"- 

3" from the end = 1.932" ) Minimum difference = o.ooi" 
i' 6" " ^ 1.932' ) 

^ '92 t Maximum difference = 0.005" 

7' " =1-935"' 

It will be found that there are few kinds of shaft couplings that will take 
in and join two lengths of shafting that are not both of the same diameter, 
and generally that diameter must be absolutely that for which the coupling is 
made. Variations of 1-200 of an inch in diameter are very common, and 
differences of i-ioo inch are to be found in any large shop. The surface of 
turned shafting should be uniformly true and good throughout the entire 
length, so that pulleys can be fastened on at any point. 

One fault that is very common in shafting coming from shops that have 
no special and first-class appliances for making shafting, is that the lengths 
are not straight. They may be perfectly round, all of one size throughout 



190 TRANSMISSION— SHAFTING. 

their entire length, and all of the lengths may be of the same diameter; but 
the lengths may be crooked. It is useless for the buyer of shafting to try to 
straighten it, for even if he succeeds in getting it into line, as far as he can 
judge, there will be a strain upon the shaft itself, and upon the hangers and 
belts and the bearings of the pulleys driven from the shaft, which will work 
injury and consume power. 

Cold-Rolled Shafting. — There is one great disadvantage inseparable 
from the manufacture of turned shafting, and that is, that the very best and 
strongest portion is turned off. In most wrought or cast iron the skin is the 
life of the whole piece. In cast iron, the skin is very much harder than any 
other portion of the piece, and in rolled iron, the outside layers, having been 
subjected more to the condensing action of the rolls than the interior, are often 
more compact, dense and resistant. This outer part, not having a good 
enough surface for the purpose of shafting, must be thus worked down so as 
to give the largest possible finished bar, known as turned shafting. Of course 
there is the expense of turning, which must be borne by the purchaser, and the 
loss of a certain diameter and weight, which necessitates buying a larger bar. 
One step in the right direction which does away with the waste of time, 
metal and money in turning shafting is to re-roll it cold, so that the surface 
is powerfully condensed and finished finely. The results of such an opera- 
tion are that the shafting is much stronger for a given diameter, and each 
size is exactly what it represents itself to be. But there is one objection to 
cold rolled shafting for some circumstances, and that is that the interior or 
core is in such a condition of strain that if any portion of this stress is 
removed, the whole bar is thrown out of shape. Thus if it is desired to key- 
seat or spline a line of cold-rolled shafting for any great length (as for use 
in saw mill carriages, &c.), the whole will spring into a bow, and of course 
be of no use for that purpose. 

Hot-Rolled Shafting, — There is one step farther and in the right 
direction, and that is in the manufacture of hot-rolled iron shafting, in which 
the round iron bar, instead of being left with an ordinary surface which has to 
be re-rolled cold, or turned off, is subjected, while yet hot, to the finishing 
action of burnishing rolls or disks, which give it a fine surface, while 
at the same time it is claimed to be stronger for a given diameter. 
In the process of manufacture it is usual to have a small quantity of 
water to play upon the finishing rolls, and to keep things cool, and the effect 
of this is to make a small quantity of steam, which oxidizes the surface of 
the shafting, and forms a rust-proof coating of oxide of iron which is very 
sightly and useful. Hot-rolled shafting is capable of being key-seated the 
same as the turned. The thin film of the oxide of iron which covers the 
surface is the most effectual protection against rust that is known. It cor- 
responds to the coating put on by the process known as " Barffing," invented 
by Professor Barff for the protection of ornamental objects of iron work, ex- 
cept that the Barff process consists in subjecting the objects to the exposure 
in a chamber containing superheated steam at high pressure and temperature. 
This film is not only not destroyed by oxygen, but is not removable by ordi- 
nary abrasion. 



ROLLED SHAFTING— HOLLOW SHAFTS— HANGERS. 191 

Hollow Shafts, — We have considered, so far, the materials ordinarily- 
employed, and have mentioned only those shafts in which the material is dis- 
posed in a solid form. Where great stiffness and lightness are demanded 
in the shaft, it should be tubular, because the same weight of metal disposed 
in a tubular form is very much stiffer to resist lateral bending than if put in 
solid, and when it comes to resisting torsion or twisting, you can readily see 
that a plate of iron a quarter of an inch thick and a foot wide will resist 
twisting better if disposed in the form of a ring or tube than if coiled up solid 
into a bar. The nearer metal is to the centre of a shaft the less is its power 
to resist either springing or twisting. This does not mean that a 2\ inch 
tubular shaft will be as stiff and as strong as a 2\ inch solid shafting ; but if 
the same weight of metal was disposed in a tubular form it would be stiffer 
and stronger than if rolled up solid. The lighter a shaft is, other things 
being equal, the weaker it is ; that is, the less horse-power it can transmit 
and the more it will spring by its own weight, by the weight of the couplings 
and pulleys upon it, and by the thrust of gears or the pull of belts. 

But there is one thing about shafting. A shaft of half the weight, running 
at twice the speed, will transmit just the same amount of power as one of full 
weight and slow speed. There is, then, an actual economy, built up of many 
items, resulting from the use of shafting of small diameter running at high 
speed. First, there is economy in the purchase of the shafting itself ; second, 
a saving in the couplings, which will, of course, be of smaller size ; third, 
the hangers and other supports can be lighter ; fourth, the pulleys, transmit- 
ting a given power at high s[)eed, will be lighter than those transmitting the 
same power at a slow speed ; fifth, the belts, traveling at a higher speed to 
carry off a given horse-power, will be lighter than would be required from a 
slow running shaft ; sixth, the flooring required to support a light run of 
transmitting mechanism may be made lighter than where it has greater weight 
hung to it or supported by it from below ; seventh, modern machinery, being 
most of it of high speed, will need less counter shafting to take from a high 
speed shaft than from a slow running line. 

Hangers. — All hangers should be adjustable, so that whatever sag or 
lack of alignment may be in the building may be readily taken up as fast as 
the building settles, and whatever sag in the line cannot be taken up can be 
at least partly counteracted by the ball-and-socket bearings. 

As regards the distance between hangers, that is a question concerning 
which no rule can well be laid down. As a general thing, hangers are placed 
too far apart. The disadvantage of having a great distance between hangers 
is that the shafting, no matter how strong and stiff, will sag of its own weight ; 
and, secondly, every time that it makes a revolution, every part of this mass, 
and especially those portions which lie near the surface, becomes subjected 
to a wrenching motion tending to weaken the shaft, while, at the same time, 
this constant pounding consumes power. 

If you were shown an inch and a quarter shaft hung sixteen feet between 
hangers, and were told to bend it a quarter of an inch out of true, 175 times a 
minute, you would conclude that you would have to rig up some especial 
jigging machine with a good broad belt to it in order to do this ; and yet, 



192 



TRA NSMISSION—SHA F TING. 



whenever you drive a line of shafting too wide between hangers, especially 
if it is loaded with heavy pulleys and pulled upon by powerful machines 
below it, you are wasting just as much power as your jigging machine would 
require to drive it. The driving belt would have to be extra wide in order to 
drive a line of sagging shaft. This difficulty with shafting is increased by the 
sagging of the floor or other supports to which the hangers are attached. 
Hangers may be placed so close together that the shafting will spring very little 
between them. But if a heavy machine, like a set of bran rolls, weighing 
3,200 pounds, is put on the floor directly above one of these hangers, it will be 
seen that the line of shafting must be somewhat sagged by the springing of 
the floor, and more power will be consumed to drive it than before. These 
are facts which are not only self evident, but have been proved time and 
time again by the indicator and the friction brake. 

Bearings.— As regards the bearings of shafting, they can hardly be 
made too long. A two-inch shaft should not have less than seven-inch bear- 
ings ; although only first-class establishments turn out hangers having any 
such length of bearing surface. Next to the length of the bearing surface 




Fig. 78.— Pivot-Box. 



Fig. 79. — JouRNAL-Box. 



comes the question of the material of the bearings. Phosphor bronze anti- 
friction metal is probably the best in which a shaft can run. It will wear 
longer, take less oil and preserve the shaft better than anything else. But 
there are many places where it cannot be obtained, and next to it comes 
babbitt-metal (that is, real babbitt-metal), as the proper thing to use. There 
are a great many pigs of cheap lead alloys sold under the name of babbitt- 
metal, and which it is a waste of money to buy.* 

Figure 78 is a. strong form of pivot-box for shafting. Figure 79 is the 
ordinary journal-box in which the shaft extends into and below the plate. 

Figure 80 shows boxes entirely above the plate. 

Figure 81 shows a rigid self-oiling post journal-box for heavy line 
shafts. 



* Very often it is found, in changing a length of shafting from one position to another, that the coup- 
ling or the bearing or the pulley bore is too large or too small. This is because the job was made 
either by the old style of mill wrighting, where each day's work was a job by itself, to be considered 
entirely independent of any other job that had been or wou d be done on the same or different class of 
work, or perhaps was done in some "slouch shop" where they are too mean or too careless to have 
a standard system of gauges ; or, giving the establishment or establishments from which the shafting 
and the coupling and the hangers and the brasses came from, all due credit, perhaps they had been 
using their standard gauges for actual measurement, instead of keeping them free from wear to compare 
copies made from them for every day use.. 



BEARINGS— TORSION— CO UP LINGS. 



193 



Torsion. — If we know the force in pounds per square inch that it takes 
to shear any material, then that required to break a cylinder of it by torsion 
would be the leverage in inches, divided into half the shearing force in 
pounds per square inch, times 3.1416 times the cube root of the cylinder area 




Fig. 80. 



in inches. A square shaft is about one and one-fifth times as strong against 
torsion as a round one, and one-fifth less than a round, hollow one of the 
same sectional area. Hollow shafts resist torsion better than solid ones of 
the same area of metal. Wrought-iron shafting, supported at eight or nine 




Fig. 81. — Self-Oiling Post Journal-Box. 

foot intervals by self-adjusting hangers, may have a diameter equal to the 
cube root of the number of horse-powers it transmits, divided by the revolu- 
tions per minute and multiplied by 125. The faster shafting revolves when 
transmitting a given number of horse-pou'ers, the less the torsional strain. 

Couplings. — In the matter of couplings there are perhaps more en- 
gineering botches perpetrated in the way of shaft couplings than in any other 
line known to mechanics. A shaft coupling should be light, strong, quickly 
applied, tight-holding, easily taken off ; should not score, dent or mark the 
shaft, nor require its mutilation by key-sets. It should hold two shafts of 
the same nominal or actual diameter with I'ust as dead-sure a grip as though 
they had been turned in one length and cut apart. It should present no pro- 
jections which would be likely to catch the belts or clothes or any other ob- 
ject. There are such couplings made, but the proportion of them to the engi- 
neering botches mentioned is not as great as one in a hundred. The ordinary 
plate coupling should be absolutely discarded. A key-seat is of no use in 
coupling. A compression coupling, properly applied, will hold the shaft 
with a grip that cannot be made to slip, and when it is taken off, the shaft 



194 



TRANSMISSION— SHAF TING. 



will be found in just as good condition as before the coupling went on 
There are some compression couplings, however, the grip of which is almost 
a permanent affair, and, while they can be put on in ten minutes, they will 
take a couple of hours to get off. 

Line shaft couplings should hold the two ends axially true, hold them 
entirely equally, and grip the entire length of shafting so tight that it will not 
work loose by the twisting and turning of the shaft. They should be readily 
applied and removed, and be light and well balanced. As lathe-turned 






<-.. 




Fig. 82. — Conveyor Col'pler and Bearing. 

shafting is apt to vary in diameter, there is a further demand for couplings 
capable of concentric and parallel closure along their entire area, each end 
being independent of the other. Flange couplings keyed to the shafts, no 
matter how good the fits are, are bound to be eccentric with the shafts. 

There is an innate wickedness in the average shaft coupling, an inborn 
tendency to get loose, split, wring off, stick fast, &c. It is not reasonable 
for any one to expect that a line of shafting will keep in good order if hung 
to the bottom of a springy floor. The shafting should not be put up before 
the fioor has received some if not all its load, especially if there be heavy 
machines above it, which will, when put up, tend to sag the floor. Where 




Fig. 83. — Scarf-Spliced Shaft. 

the shafting is attached to cast-iron columns supporting the floor, there is 
less trouble from sagging, either when the first load is put on the floor or 
afterward when the building settles. The hanger adds nothing to the tor- 
sional resistance of the shaft which it supports. This torsional strength 
depends upon the length and diameter of the shaft. Some recommend that 
fly-wheels be put on long lines of shafting, as tending, in a great measure, to 
equalize the strain of transmission. Some recommend oiling the coupling 
boxes to diminish friction. 



COUPLINGS. 



195 



Figure 82 shows a form of coupler intended for connecting two lengths 
of conveyor shafts, although the same arrangements answer admirably for 
water-wheel shafts. The bracket which supports it is shown alongside. 

Figure 83 shows how to splice a shaft with a scarf. 

Figure 84 shows a very common form of plate coupling, each half of 
which is keyed upon the shaft, the two halves being bolted together. It has the 
disadvantage of being heavy and dangerous, and disfiguring the shafts at the 




Fig. 84. — Plate Coupling. 



ends. It is not, however, as dangerous, by reason of catching belts or cloth- 
ing, as though there were no projecting flanges or rims extending beyond 
the heads of the bolts. 

Figure 85 is a spiral coupler or clutch, a form to be preferred to the 




Fig. 85. — Spiral Clutch. 

finger clutch, as being more easily coupled, and with less noise, than the 
finger clutch when in motion. 




Fig. 86. — Finger Clutch. 



Figure 86 is a finger coupler or finger clutch for connecting or discon- 
necting the ends of two parallel shafts. 



196 



TRANSMISSION— SHAFTING. 



Figure 87 shows a wing cushion for the ends of water-wheel shafts, 
construction is clearly shown. 



Its 




Fig. 87. — Wing Gudgeon. 



In figure 88 is illustrated a coupling gudgeon which serves the double 
purpose of gudgeon and coupler. 




Fig. 88. — Coupling Gudgeon. 

Figure 89 shows a plate gudgeon for the ends of water-wheel shafts. 






%</=7 \l>^- 




^-' \ 



Fig. 



-Plate Gudgeon. 



Friction Clutch.. — In Fig. 90 is shown an adjustable device for mill 
spindles,* or any machinery driven by a shaft, where it is necessary or 
desirable to stop or start the machinery without interfering with the motion 
of shaft. 

A is the driving shaft, to which the hub and disc B is keyed fast. 
The discs C and D are fitted to clamp to the disc B, and are held firmly by 
the powerful pressure of a number of spiral springs, E, producing severe 
friction between the discs. Disc C is provided with half coupling, C ; when 
it is intended to engage or disengage motion, the hand-wheel G must be 
turned (or lever can be used), which, by means of right and left screws 

*John A. Hafner, Pittsburg, Pa. 



FRICTION CLUTCH. 



197 



forces the V-shaped coulter wheels, F F, between the discs C and D, thus 
separating them and permitting the centre disc, B, to revolve freely. This 
releases the power and stops the discs D and C, so that the half coupling 
H can be engaged with the extension of the half coupling C, thus 
communicating motion to the machinery driven by the shaft, I. The clutch 




Fig. go. — Friction Clutch. 

should be held open only long enough to engage or disengage half coupling 
H, and then allowed to close and run, whether driving shafi, I, or not ; thus 
there will be no wear on the working parts of the clutch. When the clutch 
is not being operated, the hand-wheel G is supported by the rest, K, so 
that both V-shaped wheels, F F, are entirely clear of discs. The rim of 
the clutch is provided with safety flanges, extending beyond the end of the 
springs, to prevent all risk to any one standing near or operating it. This 
clutch, it is claimed, can never get out of order, and can be regulated for 
any desired work or power by the number and strength of the springs which 
clamp the discs together. 




Fig. 91. — Clutches on Line Shaft. 



Fig. 91 shows the clutches on a line shaft. The hub of the disc C is 
turned off, instead of having the half coupling C, and to it the driving bevel 
wheel is keyed fast. The hand-wheel G is connected with the left hand- 



198 TRANSMISSION— SHAFTING. 

wheel on the grinding floor, so as to operate the clutch, thus stopping the 
wheel. By turning the right hand-wheel, it will either raise the pinion out of 
gear or put it in gear, as the case may be. When the miller loosens the first 
hand-wheel, the clutch closes, starting the driving wheel and running with 
the shaft, whether it is driving the stone or not. Thus, there is no wear on 
the working parts of the clutch, and the miller can lighten, start or stop any 
stone in the mill, and raise the pinion out of, or put it in gear, alone, while 
on the floor, without stopping the engine. 

To Liine up Shafting.^Hang a nut or other small weight over the 
ends of the shaft, by a piece of small twine, so the line passes over the exact 
centre of the shaft, and the nut is within six inches of the floor. Hang at 
each bearing or hanger, by pieces of twine, a nut from one side of the shaft, 
so the nuts are all six inches from the floor. Now stretch a line, one foot 
high from the floor, from beyond each of the end lines, exactly touching 
them. The end lines are plumb from the centre of the shaft, and the side 
lines are plumb from the sides of the shaft. The side lines, when the shaft 
is in line, must be one-half the diameter of the shaft from the straight line ; 
so move the shaft until the side lines are at that distance ; then with a short 
spirit-level level up the shaft from end to end, and go over each twice, and 
your shafts will be exactly in line. This can be done at any time, without 
trouble or expense. 

Keys. — In most cases, steel is preferable for small keys, but in some 
situations soft iron is better, as it hugs the shaft closer than a harder metal 
can. In olden times, on large water-wheels, there used to be an octagonal 
hole in the hub, and the shaft, which was correspondingly octagonal, was 
keyed up by keys driven in alternately from one side and the other. In this 
way the centre was keyed up evenly all around. Taper keys will throw any 
shaft out of centre. The straight keys or feathers will not hold anything in 
place endwise which will not hold itself without such feathers. Still, the 
taper will lock a movable fit, which the feather will not do, and will also do 
the only thing a straight key will do, which is to act as a driver. 

The entire length of all shafts carrying pulleys or wheels should be 
turned. Set-screws are a constant source of trouble. The point, only, carries 
the power, and this often either breaks off or cuts a ring in the shaft. 



CHAPTER XII. 

TRANSMISSION BY BELTING. 



Belts vs. Gears — Elements in Belt Transmission — Rubber Belts — Cotton — Rawhide — Leather — 
Duration — Requisites for Successful Belt Transmission — Tension — Sag — Tightening Pulleys — 
Lacing — Putting on Belts — Testing Strength and Grip — Laying Out — Carrying Power around 
a Corner by a Belt — Shifter. 

The almost exclusive use of belts instead of shafts and gears (even the' 
largest), as a mode of transmission of power, is a successful American inno- 
vation which has long struck foreign engineers with wonder, but which is now 
becoming more and more generally introduced, especially where there is com- 
petition with American machines. This substitution of belts for gears, even 
where accuracy in number of revolutions is essential, is largely due to the 
superiority of American over foreign belts (except in rubber) — this rendering 
possible a certainty of force otherwise unattainable. 

Belts VS. Gears. — Belts are superior to gears for the transmission of 
power in all cases where the power is irregular. They have the disadvantage 
of needing more frequent repairs than gears, and of having to be renewed 
much more frequently. One advantage of belt transmission is that connec- 
tions may be very readily established or broken at any distance and under 
any circumstances. Belts should be used instead of gearing : When shafts 
are very far apart ; when there is danger of jamming in machines which are 
run by conveyed power ; when high velocities are used ; on any machine 
that does not require excessive power for its size and extremely steady 
motion ; in conveying power from story to story in mills, etc., where there is 
any jarring in the machine ; or in running tools, so that if the tools catch, 
belts will slip instead. 

Elements in Belt Transmission. — The elements to be considered 
in belt-driving are pulley diameter, material, crown, condition, revolutions 
per minute; belt material, condition, tension, arc of contact, thickness, 
width, lineal speed per minute ; distance between pulley centres, position of 
belt, whether horisontal, inclined or vertical ; and whether opened or 
crossed ; and if a single leather belt, which side is run next the pulley. 

In belt transmission, three forces are principally concerned : the tension 
on the driving side, the tension of the driven side, and the adhesion to the 
pulleys. A. B. Couch puts the whole science of belt-driving very nicely 
when he says that the difference between the first and the second of these 
forces is the net force of transmission, and cannot exceed the third. 

That arc of contact has often more to do with the driving power of belts 
than the contact area, is shown by the wire rope, where the area of contact 



200 TRANSMISSION B V BEL TING. 

is so small as to be neglected in calculations, while large arc of contact is 
absolutely necessary. 

When we say friction of the belts upon the pulleys, we do not of course 
mean adhesion to the pulley. While the one is an absolute necessity, the other 
is the cause of waste of j)0wer. As the resistance to bending is no small 
matter, it is for this reason better to use broad thin belts than narrow thick 
ones, and as the resistance to bending decreases as the diameter of the pulley 
increases, it is for this reason better to use large pulleys, other things being 
equal. If a leather belt is dry, its adhesion is less than if it were moist. 
When moist with water, its adhesion is greater than when animal oil is 
used. 

Rubber Belts. — Never under any circumstances let animal oil touch 
a rubber belt. Mineral oils are even worse, as the naphtha, benzine, etc., 
which they contain are solvents of rubber. If a rubber belt should slip, the 
trouble may be lessened or cured by giving it a light coating of boiled linseed 
oil. If one coating does not completely remedy the fault, try another. "The 
durability of rubber belts may be increased by giving the surface a light coat 
of a composition made of blacklead (graphite, plumbago) and litharge, equal 
parts, mixed with boiled linseed oil and enough Japan to make it dry quickly. 
This will give a highly polished surface which will bed itself well down to 
the pulley." Qualities vary greatly, even although prices may be the same, 
or nearly so. Always buy the best quality (there are three grades made by 
some manufacturers). 

Cotton Belts. — These should be closely woven of the best material. If 
well waxed they have a high tractile power and wear well. Their light weight 
prevents their lifting from centrifugal force. They are apt to give trouble 
from stretching, although some makes are guaranteed against this. 

" RawMde" Belting. — " Rawhide" belting and lace leather are manu- 
factured by a process which differs from that by which oak-tanned leather 
is made. This leather is not tanned, but is first cured and dressed in oil, etc. 
The belting is made from green-salted butcher hides, from which the hair is 
sweated off instead of limed as by the old process. The skins are then cured 
in a mixture which it is said opens the pores, and when in a semi-dry or samiel 
condition they are filled with a mixture of tanners' oil and tar, making them 
at the same time pliable and waterproof. It is claimed that there are no acids 
nor lime used in its manufacture, and so it cannot eat itself up. The round 
rawhide belting made by this same process is in fact a rope, made from strips 
(selected) or strands laid up as an ordinary rope, and is really very pliable — 
a great desideratum in round belting. Belting of this class is made by the 
Chicago Rawhide Manufacturing Company. 

IJeatlier Belts. — Leather belts are the most common, and the most 
generally adaptable. The best leather for belting is oak-tanned. There is 
some belting in the market which is chemical-tanned, but colored in imita- 
tion of oak. Good hides may be spoiled in the currying. Leather belts 
weigh when new about 60 pounds per cubic foot. After that they get a very 
little heavier. 



RUBBER AND LEATHER BELTS, ETC. 201 

Duration of Belts. — Leather belts, if well taken care of and used, 
will last twenty years ; rubber eight or ten. One advantage of leather belts 
is that wide ones can be cut up into narrow ones, and old ones worked up 
into new. They stand the action of oil, heat, freezing and tearing in 
machinery better than rubber. Young hides make better belts than old ones. 
For dry, warm places, belts of coarse, loose leather may be employed ; for 
wet or moist situations the finest and firmest stock should be used. They 
should be run with the slack side on top. Long belts are better than short 
ones, except where they are vertical ; broad thin ones better for some reasons 
than narrow thick ones of the same sectional area. There is no use in 
discarding a belt so long as there are portions of it that can be used to 
advantage in another place. But new portions must not be put into the old 
one, as the tension is different. 

Requisites for Successful Belt Transmission. — The success- 
ful and economical transmission of power by " wrapping connectors " 
demands great width and large arc of belt and pulley contact ; very 
slight crowning and very great smoothness of the pulley faces ; that the belt 
shall neither slip nor stick ; that the tension be neither too great nor too little ; 
that the fastenings be strong and neat ; the laps so disposed that the driving 
motion run with, not against, them ; the belts carefully put on and skillfully 
joined ; the pulleys as large, the speed as high, and the belt as light as practi- 
cable, and the upper belt fold be slack ; the fly-wheel of sufficient weight ; the 
belt uniform in section, weight, and texture ; its edges smooth, especially for 
high running ; the pulleys lagged with paper, rubber or leather ; single belts 
reinforced on their outer edges. Belting should be pliable, so as to cling to 
the pulley and run with little friction. Oiling causes leather belts to stretch. 
Single leather belting should stand 750 pounds per inch of width, and transmit 
55 pounds on smooth, high-speed pulleys. A belt surface corresponding to 
600 feet an inch wide, or say 50 square feet in any proportions, passing in a 
minute with a half-turn around a smooth turned iron pulley of not too small 
diameter, is said to transmit one horse-power. If once strained by over-work 
a belt will soon become useless ; for this reason wide belts are to be 
preferred. Wide belts drive better than narrow ones, but not in proportion 
to the excess of width ; especially on small pulleys. One 6" belt does not 
drive as well as two 3", nor twice as one 3". Double belts, though stronger 
than single, have not twice their driving power. To carry same power they 
need to be 3-5 as wide as single. Loss of driving power is largely because 
of curling up of the edges, which may be prevented by adding a stiffening 
piece at each edge of a single belt, thus : 



New belts (especially leather) do not bed themselves as well to the 
pulley face as when older. When stiff, or glazed over, or greasy, leather 
belts again lose driving power. Increase of belt speed increases driving 
power, but not proportionately, because excessive speed causes flapping and 
two little often causes slip. Fast belt speeds are better than slow on^s for 
many reasons ; one is, they are less liable to slip, and the grip is much 



202 TRANSMISSION BY BELTING. 

better. Increase of tension increases driving power, but not proportionately. 
When bearings are ample and efficient, tension may be greater than where 
poor and insufficient (see special remarks on tightening). The greater the 
arc of contact the better the drive, but not proportionately. 

Experiments made by the author show that when new leather belts are 
run on new cast or wrought iron rim pulleys, the flesh side grips the best. 
But old belts on cast-iron pulleys drive best, and last longest, grain side to. 
Belts should not be too strong. They should be strong enough to carry all 
the power that is required of them, but weak enough to break before the 
shaft, pulleys or gears. Wood-working and flouring machinery belts gen- 
erally have less driving power than others where they can remain soft and 
pliable, as the fine wood dust chokes up their pores and lessens their jjliability. 

Where narrow belts are used on small pulleys, the shafts should be about 
15 feet apart. For larger belts and larger pulleys, 20 to 25 feet will do. 
Where there are very large pulleys, 25 to 30 feet will answer. If the distance 
between the shafts be too small, there \\\{\ not be enough sag to the belt to 
make it tight ; and if they be too far apart, there will be too much tension 
upon the belt and too much pressure upon the bearings. 

In horizontal belts the under side should be the driving side, so that the 
upper side may hug the pulley by its own weight. 

Tension. — The driving power of a belt may be increased by giving the 
proper tension, where this does not exist. The best tension for a single 
leather belt, where the bearing surfaces are good and ample, is 45 to 55 lbs. 
per inch of belt width. 

In the author's regular work, as well as in the Testing Department, he 
uses Lienau Walden's Tension Registering Belt-tightener, patented May 3, 
1881 (Fig. 92). This tightens both sides of a belt alike ; puts on any 
desired tension ; shows whether belts in use are too slack or too tight ; 
prevents friction, slip, backlash, waste or loss of power and lubricants, 
weakening of belts and breaking of fastenings. Belts tightened with it 
ought to drive better and last longer than if tightened as is ordinarily done. 
It is easily and quickly applied. It is made in sizes for belts up to 6 inches, 
15 inches and 26 inches. 

Sag. — Belts have a tendency to sag edgewise, and to leave their proper 
place upon their pulleys. This is more particularly the case with belts trans- 
mitting motion between vertical shafts. When two shafts are not in parallel 
allignment, the belt from one to the other will tend to work off from one of 
the two pulleys. There are four ways of remedying this : first, by properly 
alligning the shafts; second, by placing unyielding guides at the edges of the 
belt; third, by using special tighteners, and fourth, by giving excessive crown 
to the pulleys. When belts are used to transmit motion between vertical shafts, 
the tendency of the belt to work off is aggravated by weight, and this ten- 
dency must be met by throwing the shafts out of correct line, by guiding the 
edge of the belt, or by the use of special tighteners. Between horizontal 
shafts the weight of the belt transmitting motion tends to cause or increase 
adhesion. This is not the case between vertical shafts, the belts of which 
require to be strained by tighteners. The tighteners may be swinging or 



TIGHTENING PULLEYS— SLIPPING. 



203 



sliding, and when properly designed and made the former should be pro- 
vided with an adjustment by which the pulley can be moved in the plane of 
its axis, and the housing piece should be pivoted so that the axis may be 
given an oblique position. 

Tightening Pulleys. — The friction of a belt upon a pulley depends 
upon the pressure or tightness, and upon the number of degrees of contact. 
Generally, belts running from a large to a small pulley slip on the large and not 
on the small one. Tightening pulleys are placed on the slack side of the belt 
near the small pulley. They increase the friction of driving. They should 
always be as large in diameter and as free as possible. The best tightener 




Fig. 92. — Walden's Belt Clamps. 



is the weight of the belt on the slack side. Loose belts last longer than tight 
ones. Horizontal and inclined belts are better than vertical and short ones, 
as requiring less tightening. Fig. 93, on following page, shows an improved 
tightener, made by the Richmond City Mill Works. 

Slipping. — A belt should never be allowed to screech on the pulleys. 
This causes heating and stretching of the belt. A screeching belt should 
be hunted up at once and fixed. One writer says : " If rubber belts 

14 



204 



TRANSMISSION B Y BEL TING. 



grow glassy and slip so as to let down the motion of the machinery, 
rub them well on the inside with boiled linseed oil — the older and stickier 
the better. It will not hurt the rubber and will stop the slipping. If 
the rubber coating wears off, leaving the cotton web exposed to wear, give 
them two or three coats of white lead paint. Put in plenty of Japan dryer, 
and it will be found that the belt will wear as well and nearly as long as 
when first put on. If leather belts are smooth and slippery, a grease made 
of one part of kidney tallow and two parts of castor-oil (which is a good 
lubricant, too,* and it can be had cheap of the oilmen or at large drug and 
paint shops), put on quite warm after the belt has been moistened to open 
up the pores, will help them vastly. It is a good thing also where there are 
rats and mice, as they will not gnaw a belt that has this composition on it." 




Fig. 93. — Improved Belt Tightener. 



Belt Stretching. — A. G. writes to the Millers Journal: " It rarely 
happens that a man complains that he is getting more stuff than he has paid 
for, but really I am so much annoyed by my new leather belts stretching that 
I think I ought to ask if it is not the belting manufacturer's place to take out 
all the stretch there is before I get it, just as much as it is the tailor's jilace 
to shrink the cloth for my trousers all it will shrink before he makes it up. 
In any case, what is the best way for me to get a good stretch on them when 
they are being put on the pulleys?" To this the answer was : " The stretch 



♦Denied in toto by the author. Castor-oil is not a good lubricant. 



STRETCHING— CEMENT— SPLICE—LACING. 205 

of leather belts should be taken out of them in the process of manufacture, but 
it is often necessary to tighten even the best of them, or take up their slack 
or stretch. This is best done with two iron or wooden screw clamps with a 
right and left handed screw rod in the centre (or better yet, one such screw 
rod at each end to connect the clamps, which brings the belt edge nearer). 
The clamps may be mounted in a frame which acts simply as a guide." The 
author uses belt clamps having on each side a spring balance, enabling him 
to tighten both sides alike (Fig. 92), and to put on the proper tension — say 
forty-five pounds for each inch of width of single leather belt. 

Cement for Leather Belting, — One who has tried everything says 
that after an experience of fifteen years he has found nothing to equal the 
following as a cement for leather belting : Common glue and isinglass, equal 
parts, soaked for ten hours in just enough water to cover them. Bring grad- 
ually to a boiling heat and add pure tannin until the whole becomes ropy, or 
appears like the white of eggs. Buff off the surfaces to be joined, apply this 
cement warm, and clamp firmly. 

The Splice. — It has been asked. Which way should the splices or laps 
of a belt be run ? J. H. Cooper, in reply thereto, says : " The general answer 
to this question is. Put the belt on so that the pulley in slipping on the face 
of the belt shall run with and not against the splices. But if the belt slips on 
both pulleys, of a belted pair, then, as 'Machinist' says, there can be no 
difference which way the splices of the belt lie, for the motion of one pulley 
will be against and the motion of the other will be with the splices, which is 
a true state of the case, but which does not often happen ; there will mostly 
be conditions favoring slippage on the one or other of the pulleys, and when 
it is known which one it is, then put the belt on to suit this condition. In 
the cases where there is no slipping, if the driving pulley acts favorably on the 
splices, then the driven pulley is sure to be against them, and so it may be 
said there is really nothing in the advice directing the way a belt should be 
run, except for the cases of known slippage." 

A good rule for the distance between shafts connected by belts is that the 
distance between the shafts be ten times the diameter of the small pulley. 
We may say for narrow belts over small pulleys 15 feet is a good average ; for 
larger belts on larger pulleys, 20 to 25 feet. In every case the distance should 
be such as to give the belt a gentle sag. Belts should be enclosed in neat 
boxes on each floor. The " Washburn A" mill is the only one in the country 
driven entirely by belting. 

Lacing. — Belts should have only one laced joint. If they must be made 
of several pieces, only one of the joints should be laced, the ends of the 
others being beveled (if of leather) and permanently fastened. Fish glue 
will not splice old, oily belts. The ends of the belt must always be cut square. 
To cut and join a belt do not take it off the pulley unless necessary. Lace 
leather will pull and stretch under a straight edge. 

The belts should be placed on the pulleys as tight as possible. This can 
be best done by the use of belt clamps, except in the case of very narrow 
belts. In all cases the belt should be cut about one eighth of an inch less 
than the distance around the pulleys with the tape line. The seam of the 



208 



TRANSMISSION BY BELTING. 



The following are the results of tests by the author on the belting of the New 
York Belting and Packing Co., 37 Park Row, N. Y., expressly for this work : 











Dist. 












Width 




betw'n 


Broke- 


Strength 


Strength, 


Date. 


No. 


Inches. 


Plies. 


Grips- 
Inches. 


Pounds. 


per Inch 
wide— lbs. 


Inch Wide, 
I Ply-lbs. 


Mar. 4 


I 


2 


3 


8 


1,690 


845 


281.66 


April 28 


2 


2 


2 


8 


1,190 


595 


297 


5 


ti 


3 


3 


4 


8 


3.030 


lOIO 


252 


5 


' ' 


4 


4 


3 


8 


3,030 


757 5 


252 


5 




5 


4 


2 


8 


i>95o 


487-5 


243 


75 




6 


4 


4 


8 


3,750 


937-5 


234 


37 


t > 


7 


8 


4 


8 


6,540 


817.5 


204 


37 


* * 


8 


12 


4 


S 


8,520 


710 


177 


5 




9 


12 


3 


8 


6,400 


533-5 


177 


76 


May 4 


10 


6 


4 


8 


5,010 


835 


208 


75 

1 



Average. 233.24 lbs. 

GRIP TESTS OF NEW YORK BELTING AND PACKING COMPANY'S 

RUBBER BELTS. 





c 

OJ 














ji 


j= 


C 


c . 
-c.2^ 




-A 


J3 


g 






cn 







U L. - 


m 


" " S 




s 





ctf 




C . 


-C 




B 


c S ■" 


G C 


c c 2 




3 


□ 






to 
OS 

he 





J2 


0^ 


g.£-a 

•0 cS 


.« 4) 


per i 
lb. te 
quad 




iE 


T3 

5 


9-S 


y 


" 




C 


•s-l 


9ft = 




•F"aj ID 


Q 





0- 


£ 


<; 


H 











0^ 
-38 


o°-°- 


July 28 


1599 


3>^ 


36 


4 


90 


195 


260 


74.28 


74-28 


•38 




1600 


3% 


36 


4 


go 


400 


366 


104-57 


104.57 


-27 


-27 




I60I 


zVz 


36 


4 


180 


195 


460 


131.42 


65-71 


.67 


-33 




1602 


3K 


36 


4 


180 


400 


805 


230. 


115- 


•57 


.28 




1608 


2 


36 


4 


90 


195 


181 


go- 5 


90.5 


.46 


•46 




1609 


2 


36 


4 


90 


400 


332 


166. 


166. 


415 


.415 




I6I0 


2 


36 


4 


180 


^95 


387 


193-5 


96.75 


99 


•49 




I6II 


2 


36 


4 


180 


400 


605 


302.5 


151-25 


•756 


•3781 




I6I3 


6 


36 


4 


180 


195 


6gg 


116. 5 


58-25 


■59 


.29 




1614 


6 


36 


4 


180 


400 


944 


157-33 


78.66 


39 


.19 




I6I5 


6 


36 


4 


270 


195 


899 


149.83 


49-94 


.76 


.25 • 




I6I6 


6 


36 


4 


270 


400 


1294 


215.66 


71-88 


53 


•17 




I6I7 


6 


24 


4 


go 


195 


221 


36-83 


36-83 


18 


.18 




I6I8 


6 


24 


4 


90 


400 


450 


75. 


75- 


18 


.18 




I6I9 


6 


24 


4 


180 


195 


331 


55.166 


27-583 


28 


.14 




1620 


6 


24 


4 


.180 


400 


644 


107-333 


53.666 


26 


•13 




I62I 


3K 


24 


4 


90 


195 


igg 


56-85 


56.85 


29 


■29 




1622 


^y^ 


24 


4 


90 


400 


368 


105.14 


105.14 


26 


.26 




1623 


3K 


24 


4 


180 


195 


384 


109.71 ■ 


54-85 


56 


.28 




1624 


3% 


24 


4 


180 


400 


744 


212.57 


106.28 


53 


.26 




1625 


2 


24 


4 


90 


195 


224 


112. 


112. 


56 


.56 




1626 


2 


24 


4 


90 


400 


394 


197. 


197. 


49 


•49 




1627 


2 


24 


4 


180 


195 


415 


207.5 


103 - 75 I 


06 


•53 




1628 


2 


24 


4 


180 


400 


744 


372- 


186. 


93 


.46 


Sept. 13 


I75I 


6 


24 


4 


270 


150 


394 


65.66 


21 88 


436 


• 145 




1752 


6 


24 


4 


270 


200 


494 


82.33 


27.444 


411 


■ 137 




1753 


-i'A 


24 


4 


270 


150 


410 


117. 142 


39-047 


780 


.260 




1754 


3>^ 


24 


4 


270 


200 


491 


140.285 


46.761 


7or 


•233 




1755 


2 


24 


4 


270 


150 


379 


189-5 ■ 


63.166 I 


33 


• 44 




1756 


2 


24 


4 


270 


200 


495 


247-5 


82.5 I 


23 


.41 


Sept. 16 


1830 


3K 


18 


4 


go 


150 


"5 


32 857 


32.857 


2190 


.2190 




I83I 


3;^ 


18 


4 


go 


200 


160 


45-714 


45-714 


2285 


.2285 




1832 


3M 


18 


4 


1 80 


150 


192 


54-857 


27.428 


3657 


.1828 




1833 


3K 


18 


4 


180 


200 


28g 


82.571 


41.285 


4128 


.2064 



TESTS—LAYING OUT. 



209 



The following figures show the strength and driving power of ordinary and 
waterproof leather belting (made by E. F. Bradford & Co., Cincinnati) accord- 
ing to tests made by the author especially for this work : 

BREAKING TESTS OF E. F. BRADFORD & CO.'S LEATHER BELTING. 





Office 




be" 


fiS 


Breaking 


Breaking 


Date. 




Material. 


= 


.■5-g 


Strain — 


Strain, per 
inch width. 








^.s 


^.S 


lbs. 


May 6 


Il6l 


Leather. 


18 


8 


6040 


755 


June 21 


1 162 


*' 


( ( 


6 


7090 


11S1.66 




I163 


" 


'' 


8 


9100 


II37-5 


'* 


1 164 


** 


*' 


12 


11,550 


962.5 


i( 


I168 






2i 


2540 


1197.14 



Average, 1046.79. 



GRIP TESTS OF E. F. BRADFORD & CO.'S LEATHER BELTING. 





Vh* 




6 u 


a 
n 


50 i: 


ui 




J5 


nch 
3er 

on. 


S^5 . 


Date. 




Side to - 
Pulley ^ 
Face. 1 

I 


Pulley Di 
eter, inc 


U 

< 


tact, ae 
Tension, 





Grip per i 
width, 1 


Grip pen 
width, p 
quadrar 


Grip per 

width, 
lb. tens 


0525 


Sept. 9 


I7I3 


Flesh. ( 


) 24 


18 


195 


123 


20.5 


10.25 


.105 


' ' 


I7I4 


41 






' 400 


202 


33 666 


16.833 


.841 


420 


' ' 


I7I5 


Grain. * 






' 195 


115 


19.166 


9-5833 


.982 


491 




I7I6 








400 


119 


19-833 


9.9166 


.247 


123 




I7I7 


F.w.p ' 






' 195 


124 


20.666 


10.3333 


.159 


079 




I7I8 


(( t 






400 


264 


44-833 


22.4166 


.112 


056 


'* 


I7I9 


G.w.p. ' 






' .195 


99 


16.5 


8.25 


.084 


042 




1720 


.( ; I 






' 400 


200 


33-333 


16.6666 


.084 


042 


Sept. 17 


1852 


1 ( » 


' 18 




' 200 


no 


18.3333 


9.1666 


.0916 


0458 


* ' 


IB5.3 


F.w.p. ' 






200 


144 


24. 


12. 


.12 


06 


' ' 


IB54 


G. p. • 






200 


94 


15.6666 


7-8333 


-0783 


0391 




i«55 


F. p. ' 






' 200 


144 


24. 


12. 


12. 


06 



Belts should be bought of reputable dealers only, and only reliable 
makes purchased. The manufacturers above quoted are recommended with 
confidence. 

Laying Out. — In driving a line of shafting on one floor from the one 
above or below, the best results are obtained when the pulleys are of the 
same size, and not greater in diameter than twice the width of the belt, the 
vertical distance between the shaft centres being not less than three feet for 
every inch of belt width. 

Figure 96 shows the method of laying out holes upon the floor for quarter- 
turn belts. That fold of the belt which leaves the face of one pulley must 
approach the centre of the face of the other in a line at right angles to the 



210 



TRANSMISSION BY BELTING. 



axis of the latter. Where a, b, c and d intersect will be the place where the 
centres of the folds of the belt will pass when drawn tight and at rest. 

Figure 97 shows the manner of cutting holes through floors for belts. A 
B represent the floor, C the pulley, and d the drum. Drop a perpendicular 
from the centre of the pulley at e, and measure the distance, which we will 
call 30 inches. Drop a plumb-line from the floor to the centre of the drum, 





Fig. 96.— Laying Out Holes for Quarter-Turn Belts. 

as at /, and note the distance, which we will call 18 inches. At / make 
small trial hole through the floor, from which measure the distance from the 
perpendicular e^ which we will call 34 inches. Then, on the floor draw a line 
to represent the floor, A B, raise the perpendicular e, and set off the distance, 
30 inches, and describe a circle 30 inches in diameter to represent the pulley. 
Measure off 34 inches from <?, draw the perpendicular /, set off the distance. 




Fig. 97. — Cutting Holes in Floors for Straight Open Belts. 



18 inches, and describe a circle 24 inches in diameter to represent the drum 
d ; then draw the lines ^ h^ to represent the belt, and where g and // cross 



LAYING OUT. 



211 



the line A B, the holes are to be cut, about one half larger than the belt each 
way, which may be transferred from the plane to the place first mentioned. 




Fig. 98. — Method OF Driving Two Lines of Buhrs from One Shaft. 

Figure 98 shows the method of driving two lines of stone from one shaft, 
a being the hurst, cast in one piece, with timber top, and b a hurst cast in 
one piece with iron top. (The first method with timber top is preferable.) 




Fig. 99. — Quarter Twist Belt. 



In Figure 99 the centre of the pulley is 8 inches out of the path of the 
vertical line from the periphery of the drum. 



24^ MINIMUM 




Fig. 100.— Quarter Twist Belt. 

Figure 100 shows the proper arrangement of a quarter twist belt, where 
two shafts are at right angles with each other and not in the same plane, and 



212 



TRANSMISSION B V BEL TING. 



no tightener is desired. The distance between the near faces of the pulleys 
must not be less than four times the belt width, and the plane passing through 
the centre of the faces of one pulley must be tangent to that part of the faces 
of the other from which the belt is running. The pulley A, from which the 
belt deflects, should be wider than B, by 5 to 3, and should have extra crown. 





ELEVATION. 



Fig. ioi. 



Carrying Power around a Corner by a Belt. — In Figure loi 
E is the driving shaft, with tight pulley A and loose pulley B ; F the driving 
shaft with tight pulley D and loose pulley C. The pulleys are arranged in a 




Fig. 102. 

square on the plan, having for its side the diameter of the pulleys on the 
centre of the face. The belt is endless and runs in the direction of the 
arrow. The loose pulleys B C run in different directions from the shafts 



CARRYING POWER AROUND A CORNER. 



213 



which carry them, but they carry the slack fold of the belt and are relieved 
of heavy strain on the shafts. This is good for wide belts, with shafts ten 
belt widths apart, and is very good for carrying power around a corner by a 
belt. 

In Figures 102 and 103, the driving face of the belt is changed between 
the pulleys D and E. This may be avoided by giving the belt a half twist, 




Fig. 



but at the expense of injuring the belt more than by using both sides. Col- 
lars (O O) are placed over the pulleys B C, and there are stationary flanges 
(D N) on the uprights under the pulleys. These turn the belts back on the 
pulley faces, instead of tending to lift and turn belts over, as in the case of 
flanges fast to pulleys. 




Fig. 104. 



In Figure 104, A is the horizontal main line shaft, B the driven pulley on 
a mill spindle or upright shaft, C a tightener on a shaft parallel to the main 
shaft, with bearings, in a frame which can be raised or lowered with the pul- 
ley when the pulley B is to be stopped or started. D is a guide pulley in fixed 
bearings. This plan may be used when the pulley A cannot be placed on the 
main line shaft so as to receive the belt directly from B, as in Figure 103. 



214 



TRANSMISSION BY BELTING. 



In Figures 105 and 106 is shown a very common method of carrying power 
from a shaft to others at right angles with it. A is the driving pulley on the 
main shaft F H; D and E driven pulleys on the counters at right angles to 
the main shaft. There are two upright shafts each with a loose pulley having 
its face opposite the middle of the face of A, one to the right and the other 
to the left, over which the belt is passed as shown. The belt will run either 
way. 

Figure 107 illustrates a very difficult case to treat. The shafts are not in 
the same plane, the pulleys may differ greatly in diameter, the shafts be at 





ELEVATION 



Figs. 105 AND 106. 



any angle with each other, and the belt crossed. This is done by guide pul- 
leys. The vertical cylinder staff A is secured to the flange J and held by a 
brace G to an overhead timber H. Upon this staff there are two hubs, held 
by set screws in any position, and each with a flat face to which a flanged 
bracket, C, is bolted. The upper bolt D serves as an axis about which the 
break can turn on the lower bolt E, and the slot permits the turning and 
holds the break at the inclination required by the belt. In the centre of 
the flange C there is a pin I, upon which the pulleys turn. 

In Figure 108 the shafts are at right angles but not in the same plane. 



SHIFTER. 



215 



A is the driver on the horizontal shaft ; B the driven pulley on the mill spin- 
dle, C the tightener or guide pulley, placed at the proper angle for receiving 
the belt from B and delivering it to A. It has a short shaft running in bear- 




FlG. 107. 

ings secured to a frame sliding in fixed grooves, and may be raised to tighten 
the belt. B has a wide and straight face to allow the stone to be raised and 
lowered, and to allow of lead of the belt by reason of the different positions 





Fig. 108. 

of C. A and C should be rounded on their faces. By this arrangement 
there may be very short distances between the driving and driven shafts. 

Shifter. — A good belt shifter and brake for fast running machinery is 
made by having the fast pulley solid or with one flat side, against which the 
same bell-crank lever which throws off the belt presses a wooden brake-block. 



CHAPTER XIII. 

TRANSMISSION BY CHAINS. 

Detachable Link Chain. 

Detachable Link Chain. — The use of the Ewart detachable drive- 
chain has become general in many lines of manufacture, and it is daily being 
employed to a greater extent in mills and elevators. It is a positive trans- 
mitting agent, the links being open rectangles as shown in Fig. 109, and the 
wheels on which it runs being provided with teeth that enter the links, slip- 
ping is impossible. The chain is durable and light considering its strength, 
and can be taken apart or repaired without the use of tools, but cannot 
detach when in a working position ; it will withstand exposure better than any 
other wrapping connector known 10 us, and may be run in water or any 
chemical solution that is not especially destructive to iron. 




Fig. 109. — Method of Coupling Links together. 

The links are made of malleable iron, and after being coupled in the 
chain are tested by a machine designed for the purpose, and which is found 
to detect defects that would otherwise render the use of chains uncertain. 

To obtain the best results with the detachable drive-chain it is well to 
keep the chain as taut as possible to prevent side-swaying, and to use oil on 
the joints if the chain is exposed to the weather ; if the use is inside of the 
mill or elevator no oil is required, as the dust of the grain is a good lubricant 
in itself. As the range of sizes of the Ewart chain is quite extensive, there 
being forty, varying in tensile strength from 75 lbs. to 30,000 lbs., it is hardly 
possible for a problem to be presented that cannot be solved satisfactorily, 
except where the speed is high and the side room limited. When 
the Ewart chain is employed to carry elevator buckets special links are 
inserted in the chain at required intervals, and the cups are either bolted 
or riveted thereto. The speed and distances between the buckets may be 



DETACHABLE LINK CHAIN. 



217 



the same as when leather or rubber belts are used. The chain has certain 
advantages as compared with belting : it does not require the tension, is 
cheaper, and as a rule more durable — ^it can be lengthened or shortened much 
more readily. 

These chains are made in five styles for conveying and elevating, in six for 
wheel transmission, and in five for light machinery, such as bolting cloths, 
purifiers, etc. Each of these, of course, has several kinds of attachments to 
suit the work it is required to do. Chains for elevating and conveying are 
shown in Figs, no, in, 112, 113, 114 on preceding page. 

Detachable link-belts have been in use for many years, in particular 
situations where the use of flat friction belts would not be permissible ; but 






Fig. iio. 



Fig. III. 



Fig. 



prior to 1874 these chains had been made rudely and irregularly, and they, 
together with the wheels on which they ran, were made so largely upon the 
give-and-take plan, that they were in many respects unsatisfactory, and only 
used where the use of flat frictional belts of leather, rubber or other materials 
was impossible. The principal faults of the old-fashioned driving chains 
were that they were not capable of instant repair without the use of tools, and 
it was difficult to lengthen or shorten them to suit the varying requirements 
of tension. They used to climb the sprockets and break or jump off. Re- 
pairs were not easily made by unskillful hands. The cham which is now 
made, as invented by Mr. Ewart, is intended to serve the requirements of 
those who wish wrapping connectors that will stand exposure to rain, heat, 
cold or chemicals, that will run in water and in vats containing almost all 
conceivable wet materials, as well as for ordinary vertical or inclined trans- 



218 



TRANSMISSION B V CHAINS. 



mission. The ordinary chains formerly used for driving, ran between 
sprocket wheels, having V grooves with curved depressions corresponding 
somewhat to the shape and size of the links as first made, but the elongation 
of the links very soon made the contact imperfect and unsatisfactory. The 
flat link chain, working on toothed sprocket wheels was an advance over the 
ordinary chains running in V grooves, the toothed sprocket being more sure 
to catch in the open space in the link and produce a positive transmission. 
But the faults before mentioned, that the chains were difficult to repair, 
and so on, were a great obstacle to the use of these flat link-chains, except 
where no other transmission could be employed. As at present made the 





Fig. 113. 



Fig. 114. 



chains consist of square malleable iron links having a coupling hook by 
which these links can be quickly formed into a chain of any length, the links 
being easily detachable by unskilled hands, so that if it be necessary to take 
out a link in order to shorten the cliain, or to insert a new link in place of 
one broken, the operation is easy and rapid, and the job an effective one. 
The cuts show various sizes and styles of these links as used in milling and 
for grain cleaning. 

The attachments to the chains are for the purpose of enabling sweeps, 
elevator cups, etc., to be fastened to the chain at any portion of its length. 
A number of them are shown in Figs. 115, 116, 117, 118, 119. 

" A " attachments are used to secure the ends of slats for carriers and con- 
veyors. " C " attachments are used for scrapers. " E" attachments are used to 



DETACHABLE LINK CHAIN. 



219 



carry elevator cups, two strands of chains being employed. "F "' attachments 
are employed in single strands of chain. " K " attachments are for use on 
elevators, and for single strand fiat conveyors in the same way as the "F " 
attachments are used. 

The chains should always run with the back of the coupling hook to the 
wheel, the driving sprockets striking upon the outer end of the hook. This 
leaves the links free to bend at the couplings as they pass on and off the 
wheels. Long links require larger wheels than shorter ones. With small 
wheels short links are preferable. The elongation of these chains is slight ; 
the makers state that the elongation per loo feet for average work amounts 
to only three-eighths of an inch per foot as a maximum at the end of a year. 
Tighteners are seldom employed; if desired, a roller of hard wood is sufificient. 
The weight of the chain itself acts as a tightener more thoroughly than in the 
case of light friction belts. For this reason the chains can be used in 
shorter lengths than friction belts, as the tension need not be so great. In 
fact the chains will run with as much slack as a belt would have if thrown 
from one pulley and hanging on the shaft. For vertical transmission there 
is no difficulty, as the removal of a link or two will make up for any wear. 
For vertical elevation of grains a lineal speed of about 350 feet per minute is 




Fig. 115. 



Fig. 116. 



Fig. 117. 



Fig. 118. 



Fig. 119. 



found to be the best. The chain elevator cups can wade through the material 
in the boot, and fill better than in the case of the frictional belt elevators. 
Cups are attached by bolts or rivets to the attachment links, which are 
inserted in the chain at whatever distance is desirable for the purpose. 

For lubricating the sprockets and links heavy oils are recommended if 
any are used. Blacklead and grease answer admirably. Of course, no 
lubricant is needed, and none should be used for running in grain or in flour. 

This chain is not exempt from breakage from foreign substances, such as 
crowbars or stones getting into the machinery and causing sudden stoppage. 
The sprocket wheel should have a diameter of not less than three times nor 
more than sixteen times the length of the link. For elevators, one great 
advantage of positive driven link-belts, is that they can be driven from the 
bottom as well as the top, and that they can be run slowly to pick up coarse 
or wet materials. Chain wheels are very convenient in driving conveyors. 

There are cases where the link-belt, put up by persons not having full 
knowledge and experience, has given trouble by reason of the links stretching, 
so that while the whole belt could be kept the right length by taking out a 
link from time to time as it became necessary, the pitch of the links became, by 
this stretching, too great for the pitch of the sprocket wheels on which the 
chains ran ; in such cases the trouble is because the chain or belt is too light. 

15 



CHAPTER XIV. 

TRANSMISSION BY GEARING. 

Gearing — Loss of Power through Gears — Laying out Gear Teeth — Mortise Gearing — Laying out the 

Teeth of Mortise Wheels— Gear Wheels. 

Gearing. — Gear wheels are a positive method of transmitting rotary 
motion. They have the disadvantage that they are noisy and heavy, and 
hardly adapted to very high speeds ; and the advantage that they have no slip, 
and hence transmit rotation without loss of speed. They lose some power by 
friction — the amount depending upon the design of the teeth and upon the 
accuracy with which they are made. Cut gears, or those in which the teeth 
are formed by steel cutters, are better, even if of the same proportion and 
outline than cast gears made from ordinary patterns. This is because of the 
greater regularity of the teeth. But cut gears wear faster than those in which 
the " skin " or outer surface of the casting is not removed. For large cut gears 
the best are those made by a molding machine, such as is employed by 
Poole & Hunt, Baltimore. In this system of manufacture one or two teeth 
are accurately cut as a pattern, which is used on the end of a radius bar in 
connection with an index circle, which causes the spacing to be perfectly 
accurate, one tooth of the mold being formed at a time. The expense of 
making the small pattern of one to three teeth is but slight, and large wheels 
so molded are cheaper and last longer than cut gears, while more accurate 
than ordinary cast gears. 

Loss of Power through Gears. — " Where the diameters of the gears 
at the pitch line are eight times that of the journal, the loss by transmission 
is reckoned at i^ per cent, for the driver, 1^ percent, for the driven, and i-J 
per cent, for the teeth, making 4^ per cent. With pitch circles only four 
times the diameter of the bearings the loss of power is 9 per cent. The 
quarter-turn belt, when used with the tightener, takes a different arrange- 
ment or pulley position from that where there is no idler." 

Because a gear wheel contains a great quantity of cast iron, it not neces- 
sarily strong ; a wheel is only strong when properly proportioned throughout, 
the metal being concentrated in those points where it is needed. Every 
pound of unnecessary metal put in gearing is not only an extra expense, but 
necessitates heavier parts throughout the entire transmission. 

Laying out Gear Teeth. — For the practical formation of gear 
wheels, any two of which having the same pitch will gear together, the 
author prefers the method described in xh^ Journal of the Fra7iklin Institute 
for January, 1882. 

An odontograph can be based on the fact that if the teeth of a rack have 



LA YING OUT GEAR TEETH. 



221 



their face and flanks congruent, and meeting tangentially in the pitch line, all 
gear wheels correctly gearing with this rack will correctly gear with each 
other. 

To apply this: To a bar A, Fig. 120, representing a rack, attach a zinc 
template T, of a tooth, each side consisting of two equal curves meeting in 
the pitch line. Leave a space, S, between the bar and that part of the tem- 
plate representing the tooth. Make a portion of a disk of the same curve as 
the gear wheel desired ; fasten to it a piece of zinc, /. Roll the disc B on 

A A 



aS 



B 




Fig. 120, 



the bar A, and scribe the tooth T in a number of positions on the template 
sheet / (Fig. 121). 

To prevent slip, use a watch-spring or strip of zinc, one end fastened to 
the rack, the other to the wheel plate. Cut and file the second template t — 
which ought to reach to the centre of the plate B — and have a fine centre 
hole there punched. 

For epicycloid teeth the original template must be two cycloids, developed 



,-' -B 




B - 



\. 



Fig. 121. 



by rolling on the rack, a circle with the diameter of the pitch radius of the 
smallest pinion likely to be required. For involute teeth, the rack sides 
should have an angle of 75^. For bevel wheels the curve had best be 
cycloid, with draft near the pitch line. 

Some mechanics (especially watchmakers) give the driving-wheel teeth 
greater height above the pitch line than the driver. 

Mortise Gearing. — Mortise wheels cost a trifle more than iron ones, 
but make much less noise. For making the cogs, hornbeam, hickory, maple. 



222 



TRANSMISSION B Y GEARING. 



or sugar-maple wood is used. Only the butt ends of the toughest trees should 
be taken, and the wood should have been seasoned three to five years. De- 
fecljive pieces should be excluded. Wooden cogs do away with all of the 
noise and clatter of iron wheels; they wear away when working with iron 
ones, and there will be formed a shoulder which should be cut off from time 
to time. They should be kept greased with tallow. They cannot be so well 
made by hand that the action will be uniform on all points of contact. 
Nothing but a rotary machine cutter can accomplish this result. 

Wood and iron gears work better together than wood togeflier or iron 
together. Wooden cogs should be about three times as thick as iron ones, 
though some say that an iron cog stands in the proportion of five to three in 
transmitting power, when compared with wooden ones. To order wooden 
cogs, take one out of the wheel, measure it in all its dimensions, and send 
with the order sketches like the accompanying Figure 120. 

Laying Out the Teeth, of Mortise Wheels.— "The cogs being 
fixed in the rim of the pattern wheel much larger than they are intended to 





Fig. 122. — Measurements for Cogs. 



be, the circle or pitch line is described around the face of the rough cogs, 
another circle is described within the pitch circle for the bottom of the teeth, 
and a third without it for the. extremities. After these preparations the pitch 
circle is accurately divided into the number of parts or teeth which it is 
intended to make upon the wheel, a pair of compasses are then opened out 
to the extent of one and a quarter of these divisions, and with this radius 
arcs or semicircles are struck on each side of every division, from the pitch 
line to the outward circle. Thus, the point of the compasses being set in the 
division, the curve on one side of a cog and on one side of another cog are 
described, then the point of the compass being set on the adjacent division 
the curve is described. This completes the curved portion of the cogs, and, 
being done all around, completes every tooth. The remaining portion of the 
cog within the pitch circle is bounded by two straight lines drawn from the 
points and toward the centre ; this being done also to the cogs all round, 
the wheel is set out, and the cogs after being dressed or cut down to the lines 
will be formed ready to work, every cog being of the same breadth, and the 



MORTISE GEARING. 223 

space between every one and its neighbor is exactly equal to the breadth, 
provided the compasses are opened to the extent of one division and a quar- 
ter as first described. The same rule applies to the teeth of beveled wheels 
formed upon their developed pitch lines. 

" The best mathematical and practical plans are thus presented. Mathe- 
maticians and millwrights seem to be somewhat at issue on this topic, the 
former complaining that the ' millwrights have their own nostrums, most of 
which are egregiously faulty, being little else indeed than instructions how to 
make teeth clear each other without sticking.' On the other hand, Mr. 
Buchanan, an excellent practical millwright, observes that ' the method of 
forming teeth by the arcs of circles will always enable a workman to execute 
short teeth nearer to the true form than any pattern tooth will enable him to 
do.' ' Pattern teeth,' he further observes, 'and compound curves are things 
that may on some occasions be very useful, as where the teeth are long and 
of considerable magnitude in respect to that of the wheel or pinion to which 
they belong. But in all ordinary forms of wheel-work, such operations must 
consume an immense quantity of valuable labor, to attain the same degree of 
accuracy that is at once obtained by means of circular arcs.' He also states 
that ' It is the general opinion of those who are in the practice of constructing 
mill-work, that teeth ought, if possible, never to begin to act before they 
reach the line of centres, as this mode of action is thought to occasion much 
unnecessary friction, the friction of the receding teeth being less than that 
of the approaching teeth. 

" Much- time and expense have been bestowed in some places in dressing 
the teeth of iron wheels with chisels and files, the teeth being cast large in 
the first instance to be reduced in this way to the proper shape. This method, 
according to Mr. Tredgold, is now but seldom practised, the outer surface 
of the iron, which is the hardest and smoothest for wearing, being destroyed 
by this operation, in addition to the disadvantage in point of economy and 
labor. The teeth of all wheels should, however, be carefully inspected, and 
if they are in the least irregular, should be reduced by the file and chisel. 

" It is generally recommended, in calculating the number of teeth in two 
wheels playing into each other, to make one odd tooth, sometimes called by 
millwrights a hunting cog, that the same teeth may not constantly come 
together at every revolution or given number of revolutions. This was done 
originally with the intention of distributing the wear upon wooden cogs more 
equally, and to obviate any accidental differences in the hardness or solidity 
of this yielding material. In modern cast-iron wheels the metal is of such 
uniform hardness that even in match gearing, composed of two wheels of the 
same size and number of teeth, each one of which must always engage the 
same tooth at every revolution, no material difference is observed in the wear 
of any one tooth ; on the contrary, it seems that if there be any original 
inequality in the surfaces or solidity of the teeth, they will sooner become 
adjusted to each other by their constantly returning mutual attrition at the 
irregular points of action, and for this very reason are commonly found to 
run more silently after being worn than almost any other kind of wheel-work 
constructed with ordinary accuracy." , 




Fig. 125. — Spur Shell. 



Fig. 126. — Bevel Shell 



GEAR WHEELS. 225 

Figure 123 is a wide-faced spur wheel. Figure 124 is a strong form of 
bevel wheel. Figure 125 shows the shell of a mortise wheel, with a cog 
lying beside it. Figure 126 is a bevel shell. Figure 127 is a bevel wheel 
very nearly approaching a crown wheel. 

Gear Wheels. — Gear wheels are used, First, to transmit the rotation 
from one shaft to another at a short distance. Where these shafts are 
parallel the gears are called " spur gears." Where they are at an angle they 
are usually conical, crown or bevel gears. Seco?td, To transmit motion from 
a rotating shaft to a rectilineal motion to a plain toothed surface. With this 
class the millwright has but little to do, as this form occurs in very few 
places, except in belt-tightening pulleys, and the gate of the flume in a 
water-driven mill. Third, To transmit rotation from one shaft to another 
where they are in planes perpendicular to each other. 

It is always necessary to have a certain velocity ratio, this being obtained 
by two conditions which depend one upon another : the diameter of the 
wheels and the number of their teeth. 

To find the diameters we must have the distance between the axes and 
the relations of the velocities. The radii of the pitch circles must together 
be equal to the distance between the centres of the axes, and the radii must 
be in inverse proportion to the velocities (the numbers of teeth depend- 
ing upon the radii). Where there is very great velocity ratio, we must 
employ more than two wheels to effect the change of speed or transmission 
of motion. Sometimes, for convenience in driving various lines of ma- 
chinery, a velocity ratio which might be got by two wheels is obtained by 
several. 

There are eight elements in the construction of teeth : thickness, space, 
distance, tooth-depth, number of teeth, depth of face, depth of shoulder, 
form of tooth and total depth. 

Thickness. — The thickness depends upon the force that they have to 
transmit and the material of which they are made. We must consider the 
maximum amount of force to be transmitted, and suppose it all to go upon 
one corner of one tooth. If the tooth were made of mathematical pre- 
cision, and could be so maintained, the space at the pitch line should be 
exactly equal to the thickness of the tooth. In practice it is found neces- 
sary to allow at least jV the thickness of a tooth as " play." In the most 
favorable cases, where the tooth is cast, the space should be -^^ the thick- 
ness. 

Distance. — The distance between two teeth must be equal to the thick- 
ness plus the space. It must be the same upon both wheels that gear 
together, and must be contained an exact number of times in the circum- 
ference of the pitch circle. 

Shoulder. — The shoulder is that part between the pitch circle and the 
base of the tooth. It is sometimes called the flank. Only the shoulder or flank 
should come in contact with the face of the tooth of the other wheel. Teeth 
must be deep enough to allow at least two teeth of each wheel to be in 
motion at a time. Pinions should not have less than 15 teeth. Where a 
wooden wheel meshes with an iron pinion, the wooden wheel has thicker 



226 



TRANSMISSION B V GEARING. 



teeth than the pinion, and hence the spaces on the pinion are greater than 
those on the wheel, yet the distance between the two centres must be the 
same on the two wheels. 

Breadth. — The greater the breadth the greater the strength of the gear. 
Where the gear is very wide, it is best to have the teeth divided in two parts 
laterally, the teeth in these two sections alternating with one another — the teeth 
in one section opposite the space in another. This gives smoother action. 
This is especially good for mortise wheels, giving a strong core in the middle 
of the wheel between the two mortised sections. Epicycloid gears will drive 
wheels of only one diameter, unless the generating circle has as diameter the 




Fig. 128. — Involute Gears. 



radius of the smallest pinion, and is made to roll successively upon the pitch 
circles of all the wheels that are to mesh together. 

Involute Gears. — The involute has a curve generated by the motion of 
one point of a tangent rolled about a circle. This kind of tooth works with 
wheels of several different diameters, and with wheels which have been thrust 
out of correct position of absolute contact of pitch circles. 

The thickness of the ring which carries the tooth of a cast-iron wheel 
should be equal to the thickness of the root of the tooth. This last thick- 
ness may be obtained by dividing the greatest pressure to be exerted 
between a pair of cast-iron teeth in pounds by 1,500 ; the square root of 
the product will be the least possible thickness in inches. 



GEAR V/HEELS. 227 

The least breadth may be got by dividing the greatest pressure in pounds 
by the pitch in inches and by i6o ; the quotient will be the breadth in 
inches. The path of contact of the tooth should be a straight line coincid- 
ing with the line of connection, making a constant angle with the line of 
centres, and inclined at an angle of 14^° to the common tangent of the 
pitch lines. 

Referring to the cut, Fig. 128, let, First, C represent the centre of the 
wheel, I the pitch point, C I the radius, BIB the pitch circle. We will 
suppose we are going to draw a wheel of 30 teeth. To draw the base circle 
and line of connection, take a radius, C P, equal to ff of C I ; with this, 
draw the base circle D P D with radius I P, equal to \^, the pitch radius. 
Draw a short circular arch centred in I, and cutting the base circle in P, 
draw the straight line P F I E, which is the line of connection. 

Second, To find the normal pitch, the addendum and the real radius, 
and to draw the addendum circle and the flank circle. From the pitch 
point I draw a straight line, I A, tangent to the pitch circle. From A let 
fall A E perpendicular to I E, then I E will be the normal pitch along the 
line of connection, or the distance from the front of one tooth to the front 
of the next ; or what is the same thing, the pitch or distance between tooth 
centres. 

This normal pitch will be in the same proportion to the circular pitch 
as the radius of the face circle is to the radius of the pitch circle; that is, 
I E divided by I A equals C P divided by C I = ff. 

To insure that at least two pairs of teeth shall always mesh, the arc 
of contact may consist of two halves, each equal to the pitch. Lay off 
on the line of connection, E P, the distance I F equal to I E, then E F 
will be the path of contact. A straight line from C to E will be the real 
radius. The circle EGG, with that radius, will be the addendum circle 
which the tops of all the teeth must touch. With the radius C F draw the 
circle F H. This may be called the flank circle, because it marks the inner 
ends of the flanks of all of the teeth. C E less CI is the addendum. 

To draw the root circle which the bottoms of all the tooth spaces are to 
touch, first find the greatest addendum of any wheel with which that wheel 
may have to gear. This will be the addendum of the smallest pinion of the 
same pitch and obliquity. With an obliquity of 14^° that pinion has 25 
teeth. To find the addendum of this pinion of 25 teeth through them 
parallel to P C, draw F L, cutting I C in L, join L E; the required greatest 
addendum will be L E minus L I, which is very nearly .343 of the pitch. 
Generally .35 of the pitch is used for addendum. To this greatest adden- 
dum make suitable lines for clearance, and lay off the source, I K, inward 
from the pitch circle along the radius. C K will be theradius of the root circle. 

To draw the tooth traces, mark the pitch point of the tooth front, I I', &c., 
and those of their backs, by laying off a suitable thickness on the pitch circle. 
Shape the templet accurately to the figure of the base circle. File a piece of 
watch-spring so as to leave a pair of projecting tracing points from its edges. 
Drill a round hole in one end of the spring and fix it to the middle of the 
templet edge by a screw or thumb tack. Put the templet on the drawing or 



228 GEAR WHEELS. 

pattern so as to coincide with the base circle, and so that the lower end of the 
tracing point shall pass through the pitch point of the tooth, then that tracing 
point will draw the front of the tooth. To trace the backs of the teeth, turn 
the spring over on the templet. The distance from the screw to the tracing 
point should not be less than twice the normal pitch. 

The clearing curves are the trace of the holes inside the flank circle of 
each. Their sides should be tangent to the inner ends of the flanks, and 
their bottoms should coincide with the root circle. 

The back lash also of involute teeth is variable at will. It can be increased 
by moving the wheels farther apart, and diminished by bringing them closer 
together, care being taken not to let them jam. 



W^ 



CHAPTER XV. 

TRANSMISSION— PULLEYS. 

Pulleys — Stepped Pulleys — Split Pulleys — Loose Pulleys — Idle Pulleys —Tractive Force- Lagging 

— Bevel and Mitre Friction Pulleys. 

Pulleys. — Pulleys for flat belts may be of cast iron, wrought iron, or 
wood ; and may have their faces either plain or covered with a lagging com- 
posed of leather, rubber or paper. 

The lighter a pulley is, the less it ought to cost, the less the freight bill 
on it, and the less sagging weight there will be upon the shaft. There is a 
certain way of putting metal in a cast-iron pulley which will make it light, 
stiff, and strong. There are some establishments which make pulleys noto- 
riously heavy, and others which make them as notoriously light. There is 
between these two customs what the Irishman calls the "middle ixtrame," in 
which every pound of metal is put in a certain place with an intelligent pur- 
pose. Such pulleys may be picked out of a car load by reason of their greaf 
beauty, because it strangely happens that where metal is properly put in place 
there is a grace and harmony of outline which is destroyed by any other 
system of design. The writer has found the pulleys of Poole & Hunt, 
Baltimore, strong, serviceable, and satisfactory in every way. 

Stepped Pulleys. — A millwright often has to ask himself the ques- 
tion : " How can I lay out a cone pulley so that the belts will be of the same 
tension on all the pulleys ? " Now, often he will erroneously make the 
diameters of the driving and driven shafts the same. For example : he 
wants to make a cone with the largest pulley on the driving shaft i6 inches, 
and the smallest cone on the driven shaft 7 inches diameter. These two 
diameters he adds together, making 23 inches. He now proceeds, desiring 
to make his next pulley 14 inches. This would make the next pulley on the 
driven cone 9 inches, and so on. 
This reasoning is not correct. 

The belts in these pulleys will not be of the same tension on all the steps. 
In order to thoroughly elucidate this matter, when two cones of pulleys, or 
" stepped cones," are made alike — that is, with equal steps, such that the 
sum of the diameters of each belted pair is the same, a crossed belt will run 
with equal tension on any pair so made, when the shafts are parallel and the 
cones reversed ; but an uncrossed belt will not so run on such cones. To show 
why the open belt will not have equal tension on all the pulleys, let AB, in 
Fig. 131, be two equal stepped cones on parallel axes, AE and BD. Now, 
if the sum of the diameters of the extreme pulleys E and F be equal to the 
sum of the diameters of C and D, the connecting strips EF and CD of the 
belt will be equal, because the enrolled parts are equal by the construction 



230 



TRANSMISSJON—P ULLE YS. 



of the cones ; but EF and CD cannot be equal, because they are not 
parallel, and hence it plainly appears that CD, being at right angles to the 
shafts, is shorter than EF ; therefore, to preserve a certain tension of the 
belt when on the extreme pulleys, the middle pulleys must be larger than the 
size given by equal steps, in order to take up this difference. To find the 
proper diameters of the intermediate pulleys for open belt cones, first get, 
by Rankine's rule (annexed), the radius NO from the given radii IJ, KL, 
■ and distance between shafts, and through the points J O L describe a circle 
arc, upon which draw the faces of all the pulleys in thfe series as shown. 
Make both cones by this rule, and an open belt will run upon them with 
equal tension. Unequal cones may be made in like manner by drawing two 
similar cones, and then using, say, S T V of the large end of one, and X Y Z 
of the small end of the other, as needed to serve the purpose. For wheels 
driven by round bands in V grooves the same rules apply, observing that 
the effective diameters must be taken at the line oi band contact in the grooves, 
























! V 




A ; T 




i s 








1 1 1 


:r 1 


^i 1 


"Ti 




^i 





Fig. i2g. 

which are the acting circles of .adhesion. All the grooves must be alike, and 
should have concave sides, like a Gothic arch, instead of straight, and the 
band must not touch the bottom of the groove. 

Rankine's Rule. — When the belt is uncrossed, use a pair of equal and 
similar conoids tapering opposite ways, and bulging in the middle, according 
to the following formula : Let c denote the distance between the axes of the 
conoids ; ri the radius of the larger end of each ; r2 the radius of the smaller 
end ; then the radius in the middle, ;■„ is found as follows : 



*■! -\- r2 (ri — ?-2)^ 



ft, = 



6 28<r 



Split Pulleys. — On this head the writer can hardly do better than to 
quote from the American Machinist the remarks of that humorous and prac- 
tical classic, " Chordal " : 

* * * * " My own opinion is that the split pulley is a good institution. 
Their first cost is a trifle more than a solid pulley, and they are not as hand- 



5 TEPPED P ULLE YS—SPLI T PULLE YS. 231 

some, but the cost in the end will be found to be less than solid pulleys, and 
a sort of ' functional beauty ' should result from the apparent propriety of 
the thing. 

* * * * " I know that all well regulated machine-shops have excellent 
intentions of maknig all pulley changes, etc., at night or at noon, so as not to 
interfere with work. Such good intentions are like many other good inten- 
tions around machine-shops, that is, they don't amount to much. There is 
hardly a shop in the land which don't stop in the middle of a day's work, 
time after time during the year, to do some fussing with line-shaft pulleys. 

* * * * " If a twenty-inch pulley has to be put on a shaft in a small 
shop working, say, ten men, the whole thing don't hesitate to come to a stand- 
still while the change is being made. Every man, from proprietor down to 
cub, is under the impression that he is doing something on the job himself, 
and, as a consequence, the job must be charged with the total machine-shop 
labor and expense bill for about five hours. The more men there are, the 
longer it takes to do the work. 

" It looks like a short and simple piece of work to stop a line shaft, unbolt 
couplings, loosen collars, move part of the shaft endwise, worry one of the 
couplings off, get three or four pulleys off, put the new pulley on, put the old 
ones back, worry the coupling on again, move the shaft back, put in the 
coupling bolts, tighten up collars and pulley screws, and start the machine 
again. It's mighty easy and cheap to tell about it, but it takes a long time, 
and it costs lots of money. 

****<' jj^ ^jjg f^j-gj place, something has to be cobbled up to stand 
on. Who ever saw a nice line-shaft trestle around a shop ? Then it is found 
that the coupling nuts are let into counter-seats, and that a special wrench 
must be had. Question: — ' Shall we wait for a wrench to be forged, or shall 
we get the nuts off with a chisel ?' Answer by all: — ' O! get a good wrench 
made.' The wrench is ordered, and while it is being made every last one of the 
nuts is hogged off with a chisel. You might naturally think that this wrench 
would now be laid away for future use on this same shaft job. There's where 
a mistake comes in. The wrench, so nicely laid away, cannot be found the 
next time this shaft is tinkered with, and if it was found it would have no 
effect upon these nuts which have been foliated with a cold chisel. 

" When the nuts are off it is found that the smart genius who fitted up the 
coupling labored under the impression that the bolts ought to fit the holes — 
driven in oil, you know. They were driven in oil. If they had not been 
they never could have been driven at all. The job now is to drive them out 
in oil. While one man goes for a chunk of copper, the man who ordered the 
copper proceeds to batter them out with his hammer. 

" The bolts are finally out and the shaft backed open a foot or so, after 
about a dozen interfering pulleys are hunted out and loosened. The next 
thing is to unkey the coupling. It is the case of the wrench over again. 
While the blacksmith is forging a special drift the head man is pecking at the 
key with every old drift and chisel around the place, and gets the small end 
of the key so battered up that when the special drift is done there is a double 
quantity of work for it to do. When the key comes out the coupling has to be 



232 • TRANSMISSION— PULLEYS. 

hammered off. Blocks of wood and pieces of copper are talked about, but 
some one discovers old hammer marks on the coupling, and this is taken as a 
license to pound it all to pieces. 

" By the time the coupling comes off, two or three pulleys have been 
cracked or broken by awkward back strokes. After the coupling is off the 
real work is done in two minutes. Five or six pulleys are slipped off, the 
new one slipped on, and the old ones replaced. I say the old pulleys are 
slipped off, but two or three in the lot will be found so tight that they will 
have to be slipped off with a sledge. The scientific pounding on the coup- 
ling dented the shaft some, and no one ever thinks of filing a dent out of a 
shaft till he has tried to drive something past it. 

" The entire process is now reversed, the coupling driven on, the old key 
searched for and not found, a new one ordered, the old one found in the 
meantime, the old one found to be so battered up as to be useless, all hands 
wait for the new one, head man gets tired waiting and concludes to sock the 
old ones in, does so, shaft pried into place, two bolts put in, two bolts found 
so battered up as to require a thread to be filed on them and the upset filed 
out of them, and at last the job is complete and the boys go to "work " again. 

" Total cost of putting on new pulley — cost of pulley, plus four hours' 
total expenses and labor of a small machine shop, plus four hours' idleness 
of a small machine shop. Total equals cost of half a dozen split pulleys. 

* * * * " The description I have given of this job only applies if the 
job happens to be a lucky one. Generally the shop comes to a standstill 
about an hour after the job is done ; some big belt to be put on. After a 
while another stoppage ; forgot to tighten some pulley. Another stoppage ; 
a pulley is set two inches out of place. 

" Next day there is half a stoppage. Part of the shaft stops and part 
keeps on. Some slip collar was left loose, and some loose coupling crawled 
right off of the shaft. This is easily fixed and is made an excuse for tightening 
all set-screws which have been loosened. The next day the real snarl comes. 
It is found that in replacing the old pulleys one of them got put on in the 
wrong place. There is no way out of this but to go through the whole job 
again, The only reason the second doing of the job is not as laborious as 
the first is that the fits are all fresh. 

* * * * " Split pulleys" are easily and cheaply put in place. Thirty 
minutes will generally do for placing one. The shaft is not marred by set- 
screws or other such fastenings. The couplings become simply an expedient 
to save making a shaft in one length." 

Split pulleys or couplings should have the hole bored a trifle larger than 
the shaft. The bolts will bring it to a perfect bearing. If bored too small 
the hole will only fit the shaft in two places. A slight grip al) around is 
better than a tight grip at two points only. It is claimed for wrought-iron 
split pulleys that they are lighter, stronger and more rigid than cast. The 
arms and rim are made of wrought iron, and the arms are so twisted at their 
connection with the rim that the wide part of the iron stands in the direction 
of the strain, while presenting the minimum of resistance to the atmos- 
phere in revolution. They are easy to fix on the shaft, being made in halves. 



TRACTIVE FORCE. 



233 



Neither the shafting nor the pulleys need be disturbed to attach them or 
remove them at any point. They are claimed to give increased grip be- 
tween the belt and the pulley, and transmit more power for a given diameter. 
The writer's tests prove otherwise. For exportation they should be very 
advantageous by reason of their lightness and strength, and the small space 
they occupy when apart, by reason of their being in halves. They can be 
made to any size, either round or flat on their face. Where split pulleys are 
used, the bolted portions should be put together by bolts stout enough to 
make them as strong as any other part of the pulley. 

Loose Pulleys. — Loose pulleys require constant attention and much 
oil, and are very hard on the belt. It is best to have them a trifle smaller 
than the tight pulley, and with a step or flange running up to the diameter of 
the tight one. This takes the strain off the belt and the friction from the 
pulleys. 

Idle Pulleys. — As a general rule, idle pulleys (not tighteners nor loose 
pulleys) are an excuse for bad engineering. But there are cases where it is 
absolutely necessary to carry a belt under a timber, or else to cut away the 
timber, and the latter might be expensive for several reasons besides weaken- 
ing the building. Sometimes where there is a very long belt an idler is used 
to steady the slack side, or where the belt comes too near the floor, to hold 
it up. 

Tractive Force. — The grip or driving tension of leather belts upon 
smooth turned cast-iron pulleys, was ascertained by Robert Briggs and 
H. R. Towne, to be 67 pounds per inch of width of the belt. This is about 
one-third of the known breaking strength of ordinary lacing or other belt 
joints. With equal arcs of contact the adhesion differs very little on pulleys 
of 12.24 or 42 inches diameter. The following table gives the net forces 
which have to be carried over each inch width of single leather, covering 
various arcs of contact (tension not stated) from :^ to f of the circumference. 



Arc of 


Lbs. 


Arc of 


Lbs. 


Contact. 


per inch. 


Contact. 


per inch. 


90° 


32.33 


150° 


44.64 


100° 


34.80 


180° 


49.00 


110° 


37.07 


210° 


52.52 


120° 


39.18 


240° 


55-33 


135° 


42.06 


270° 


57.58 



This table may not always be at hand, but the figures thereof may be ap- 
proximated by adding 27 to one-seventh the number of degrees of contact. 
This will give the force in pounds per inch in width of the belt. Of course 
the number of lineal feet per minute belt speed, when multiplied by this 
number of pounds strain, will give the foot pounds, from which the horse- 
power of the belt can be readily ascertained. 

In one set of experiments concerning the tractive force of smooth-faced 
pulleys, two pulleys were made, one of soft maple and the other of iron, both 
highly finished ; each 17 inches in diameter, 6 inches face, and put up as 



234 



TRANSMISSION—PULLE YS. 



shown in Fig. 130. There is a double crank, A, with two foot arms, the 
iron pulley being journaled in its upper end, having bearings i-^ inches diame- 
ter, 3 inches long, running in babbitt. The frame is held in trunnions and 
balanced by the weight B. W and B are weight boxes. The pulley face I, 
is rather wider than 6 inches, so that it may have a cord C, running in a 
groove cut around it with the centre of the cord just at the periphery. V is 
a driving pulley, running watch-wise, or from left to right. The pressure 
between the pulleys is determined by the weight W. The wooden pulley being 
set in motion, the other pulley will be rolled and the weight W raised ; the 
pressure required to raise the weight being noted, then the pressure would be 
noted which would hold the weight from slipping down. After these tests, 
the frame was reversed so that the weight in the pressure boxes would tend 
to separate the pulleys, which were connected by the 6 -inch leather belt, and 
the experiments continued. It was found that the pressure required to raise the 
weight, and that to raise it without slip, was greater in the case of the belted 
pulleys than in that of the friction pulleys ; the pressures being with a weight 




Fig. 130. 

of ten pounds raised respectively 29 and 33 pounds on the friction pulleys and 
30 and 34 pounds on the belted ; while with 180 pounds raised there were 
538 and 561 pounds with the friction pulleys and 592 and 731 with the belted. 
This shows that the friction wheels had greater traction than the belted pul- 
leys ; and that while the adhesion falls off as the work increases, the friction 
increases as the labor gets greater. As the work increases, the pressure re- 
quired to -just do the work increases in the case of the belts, while it remains 
about the same with the friction wheels. 

Lagging. — To cover slipping pulleys with leather, take a piece of belt 
leather of uniform thickness, as wide as the pulley face and as long as the 
circumference of the pulley plus the required lap and less six per cent, (this 
six per cent, scantness is to make a tight-stretched fit) ; then scarf and unite 
the lap so as not to increase the thickness when cemented together, otherwise 
the belt would drive irregularly. Draw this on by iron hooks, putting hair 
side out and putting it so that the outer end of the lap will be raised when 
the covering slips on the pulley. This is to prevent the joint opening and 



BEVEL AND MITRE FRICTION PULLEYS. 



235 



tearing. Rivet to the pulley rim, sinking the heads below the driving surface. 
Copper rivets are best. Remember that in adding a leather lagging or 
covering to a pulley, you are increasing its diameter nearly one-half an inch, 
which will slightly affect speeds and power. Belts, grain side to the pulley, 
drive about 50 per cent, more after than before the pulley was covered. Use 



•^ 



"^ 



Fig. iqi. 




a cement of three pounds of glue made up with vinegar, to which is added a 
teacupful of Venice turpentine. Leather pulley lagging cannot be used in 
damp places. 

Bevel and Mitre Friction Pulleys.— Bevel and mitre friction 
pulleys work quite well, nearly as well as if cylindrical ; having only 







m 



a 



" r'wiTJvyjw^ 






^2 



TJ 




l i uockwuop press eag. w.y. 1 i 

Fig. 133. — Wrong Form of Bevel Friction Pulley. 



this disadvantage, that their face cannot be extended very far without 
increasing the diameter. But for ten horse-power or less the bevel 
friction is very good, and especially adapted to reversing motion. There 
is an iron cone, just as for a bevel pinion, except that it has a turned 




Fig. 134. — Right Form of Bevel Friction Pulley. 



face. The rim may be a little lighter than for a pinion. To get the 
exact diameter and bevel, place a square across the smaller end of the 
finished iron pulley, and set the bevel to it, as shown in Fig. 131, which 

16 



236 TRANSMISSION— PULLEYS. 

will be the right bevel for the driver. Draw the lines AB, AC, making AB 
equal to the large diameter of the iron pulley, and the angle A 90°. Then with 
the square and bevel draw BC and AD. AC will be the diameter required 
for the driver. The other dimensions are easily obtained. For shafts at 
acute angles, draw the lines as in Fig. 132. Let AB represent the driving 
shaft ; AC, at a right angle to it, should be as long as half the diameter of the 
driving pulley. Then draw CD at an angle at which the shafts are to be set ; 
draw CE at right angles to this, as long as half the diameter of the other 
pulley. From E draw EF parallel to CD, and this will represent the other 
shaft. From the point of a section of this and the line AB draw GC, which 
will give the bevels for both pulleys. For pulleys 2^ feet in diameter or less, 
the driver may be upon hub flange about two-thirds the pulley diameter. 
Instead of this being made with a cast-iron core as shown in Fig. 133, 
there should be a hub flange along the lower side, to which the thickness of 
wood should be bolted (Fig. 134). The form of iron centre shown in Fig. 
133 is a common one, but a very bad one. 



^*^ 



CHAPTER XVI. 

ROPE TRANSMISSION. 

Location of Power— Transmission of Power by Wire Ropes — Distance of Transmission -Driving 
Ropes — Siieaves for Wire Rope — Deflection of Ropes — Long Transmissions — Rope Con- 
necting Rods. 

Rope transmission permits placing a water-power and mill up on a bank 
out of the reach of freshets — a most important consideration — and also allows 
the mill to be placed convenient to roads, etc., while the water-wheel may be 
placed to best advantage. 

Transmission of Power by Wire Ropes. — The distance to 
which this can be apphed ranges from fifty to sixty feet up to about three 
miles. It commences at a point where a belt becomes too long to be used 
profitably, and can thence be extended almost indefinitely. The power can 
be conveyed up an ascent of i in 8 or lo, or down a moderate slope as well. 

A table of horse-powers is given on following page. It embraces every 
case that will ordinarily' arise in practice, and one can readily select that com- 
bination which will suit his own case. The first column gives the diameters 
of the grooved sheave-wheels, in which the rope runs, commencing with four 
feet. Then, knowing the number of revolutions which your shaft makes, the 
last column gives the horse-power corresponding to a certain-sized wheel. 
Where there is a choice between a small wheel and fast speed, or a larger wheel 
with slower speed, it is recommended to take the larger wheel. The horse- 
powers given are minimum, and can be relied upon under all circumstances. 

Distance of Transmission. — " The foregoing table is intended for 
distances from 80 up to 350 or 400 feet in one stretch. For a single stretch 
extended to say 450 feet, where no opportunity is presented for putting in an 
intermediate station, we must use a rope one size heavier ; and in a case 
where there is not sufficient head-room to allow the rope its proper sag, and 
it has to be stretched tighter in consequence, we must also take a rope one 
size heavier. Whenever the distance is less than 80 feet, the ropt- has to be 
stretched very tight, and we no longer depend upon the sag to give it the 
requisite amount of tension. Here we must take a rope two sizes heavier 
than is given in the table, and run at the maximum speed indicated: it is also 
preferable to substitute in place of the rope of 49 wires a fine rope of 133 
wires, of the same diameter, which possesses double the flexibility, runs 
smoother, and lasts longer. In fact, the substitution of a fine rope for a 
coarse one can be done with advantage in every case in the table where the 
size admits of it. Both kinds of rope are spliced with equal facility. The 



238 ROPE TRANSMISSION. 

TABLE OF TRANSMISSION OF POWER BY STEAM. 



Diame- j 

ter of 

Wiieel ,, 
in Feet. " 


sfo. of 
Revo- 1 
ilions. 

8o 


rrade 
Mo. of 
Rope. 


Diameter 
of Rope. 


Diame- 
Horse- ter of 
Power. Wheel , 
in Feet. 


^fo. of 

Revo- 
utions. 

80 


Trade 

No. of 
Rope. 


Diameter 
of Rope. 


Horse- 
Power. 


4 


23 


/s 


3-3 


10 


19 
18 


% ^ 


55- 
58.4 


4 


lOO 


23 


H 


4-1 


10 


100 


19 

18 


% \\ 


68.7 
73- 


4 


120 


23 


H 


5- 


10 


120 


19 

18 


n \k 


82.5 
87.6 


4 


140 


23 


J^8 


5.8 


10 


140 


19 

18 


H H 


96.2 
102.2 


5 


80 


22 


7 


6.9 


II 


80 


19 
18 


rs H 


64.9 

75-5 


5 


100 


22 


A 


8.6 


II 


100 


19 
18 


H H 


81. 1 
94-4 


5 


120 


22 


tV 


10.3 






















II 


120 


19 

18 


H H 


97-3 
II3-3 


5 


140 


22 


A 


12. 1 






















II 


140 


Jt9 
18 


H H 


113.6 
132. 1 


6 


80 


21 


Vz 


10.7 










6 


100 


21 


% 


13-4 


12 


80 


18 
17 


H H 


93-4 
99-3 


6 


120 


21 


'A 


16. 1 


12 


IOC 


18 
17 


H H 


116. 7 
124. 1 


6 


140 


21 


% 


18.7 


12 


120 


18 
17 


H Ya. 


140. 1 
148.9 


7 


80 


20 




16.9 


12 


140 


18 
17 


H % 


163.5 
173-7 


7 


100 


20 


9 


21. 1 


13 


8.. 


18 
' 17 


H V^ 


112. 
122.6 


7 


120 


20 


A 


253 






18 


11 %/ 


140. 












13 


100 


17 


ri M 


1532 


7 


140 


20 


9 


29.6 






18 




168. 












13 


120 


17 


Ti ?< 


183-9 


8 


80 


19 


>^- 


22. 


14 


80 


17 
16 


^ ^8 


148. 
141. 


8 


100 


19 


>i 


27 5 










185. 
176. 












14 


100 


17 
16 


3/ ?^ 


8 


120 


• J9 


f^ 


33- 












8 


140 


19 


li 


38.5 


14 


120 


17 
16 


^ % 


222. 
211. 


9 


80 


20 
19 


A >^ 


40. 

41.5 


15 


80 


17 
16 


H Vs 


217. 
217. 


9 


100 


20 
19 


A n 


50. 
51.9 


15 


100 


17 
16 


^ ?^ 


259- 
259- 


9 


120 


20 
19 


A >^ 


60. 
62.2 


15 


120 


17 
16 


U ^ 


300. 
300. 


9 


140 


20 
19 


A ^ 


70. 
72.6 













DRIVING ROPES, ETC. 



239 



splices are all of the kind known as the long splice ; the rope is not weakened 
thereby, neither is its size increased any, and only a well-practised eye can 
detect the locality of one. 

It is not necessary that the two wheels should be at the same level, one 
may be higher or lower than the other without detriment ; and unless this 
change of level is carried to excess, there need be no change in the size of 
wheel or speed of rope ; the rope may have to be strained a little tighter. 
As the inclination from one wheel to another approaches an angle of 45°, a 
different arrangement must be made." 

Driving Ropes. — "The range in the size of wire ropes is small, vary- 
ing only from f inch to f inch diameter in a range of 3 to 250 horse-power. 
The ropes are always kept on hand, and can be spliced endless at the factory ; 
or else a man is sent to splice them whenever an endless belt cannot be put 
on direct. Where a rope-transmission has to be constantly at work, it is good 




Fig. 135. — General Idea of Sheave for Wire Rope. 

policy to keep a spare rope on hand ready spliced, so as to avoid delay. 
Their duration is from two and a half to iive years according to the speed. 
For the smaller powers it is advisable to take a size larger, for the sake of 
getting wear out of the rope, although it must be borne in mind that a larger 
rope is always stiffer than a small one, and therefore additional power is lost 
in bending it round the sheave. An illustration of that is seen in the case 
of the 1 4- foot wheel in the table, where a \ rope gives less power than a f 
rope, simply because it is so much stiffer. Ropes for this purpose are always 
made with a hemp core, to increase their pliability." Fig. 135 shows the 
proper form of sheave and groove. 

Sheaves for Wire Rope. — It is necessary that the rims and grooves 
should be turned truly, and the wheels very carefully balanced, and not only 
the groove must be filled with some kind of packing to increase the grip and 
lessen the wear of the rope, but the sides of the flanges must be protected by 



240 



ROPE TRANSMISSION. 



leather fastened by rivets. In Fig. 136, B shows this lining, which extends 
between the packing and the flanges. 

Deflection of Ropes. — "When the upper rope is the driving rope, it 
will become more or less tense on starting the power, thus causing the lower 
rope to sag from a direct line between the wheels about one half more than 
when the rope is still. This is of importance, as it should be known before- 
hand whether the lower rope is going to scrape on the ground or touch other 
obstructions. Whenever the direction of the motion of the driving wheel is 
not fixed by other circumstances, it is often advisable to make the lower rope 
the driving or pulling rope, and the upper rop^ the follower. In this way 




Fig. 136. — Lining Wire Rope Sheaves. 



obstructions can be avoided which by the other plan would have to be 
removed. In Fig. 137 the upper rope is the driver, and the lower one, 
having little or no tension, sags very far out of the horizontal. When the 
ropes are not driven, both sides take the position shown by the curved dotted 
lines. To find out how low the under rope will come when the top one 
drives, hang up a wire and let it come down about one-thirty-fifth the distance 
between the wheel-centres. The lower rope will hang about one-half more 
below the horizontal line than when at rest. The upper one, when driven, 
will hang about one-forty-fifth or one-fiftieth instead of one-thirty-fifth the 



DEFLECTION— .LONG TRANSMISSION. 



241 



distance between wheel-centres, below the horizontal line. In Fig. 138 
the lower rope is the driver and the upper one the loose rope. It will be 
seen that in this case the sag is very different from what it was in the former. 
When a rope is very long it is advisable to take up the stretch at the end of 
two or three months, as a slack rope does not run so steadily as a tight one. 
The rope while running requires no protection. If it has to stand still much, 
pour some hot coal-tar from a can on the rope in the groove of the wheel 
while running. Whenever there is no room for the sag of the rope, and it 
is inconvenient to raise the wheels higher, or a ditch cannot be dug, it may 
be supported by a roller in the middle. This supporting-roller must be in 
the middle of the span, and must be at least half the size of the larger 
vvneels." 




Fig. 137. — Upper Rope Driver. 

Long Transmissions. — " When the distance materially exceeds 350 
to 400 feet, a rope-transmission should be divided into two or more equal 
parts, by means of one or more intermediate stations. At each station there 
is a wheel mounted on a pedestal or other support, and provided with a 
double groove in the rim ; so that in place of one long continuous rope, we 
have two or more shorter endless ropes, extending from station to station. 
This is far preferable to supporting-rollers in the middle, especially when the 
demand on the power is intermittent and jerks would thereby be caused in 
the rope. With the two-grooved wheel that cannot take place : moreover, 
the wear of the rope on a supporting-pulley is greater. The whole system 




Fig. 138. — Lower Rope Driver. 



should be in a straight line from end to end. The number of stations can 
be extended indefinitely. Transmissions are in operation a mile in length. 
The loss of power from friction, etc., or bending of rope, does not amount 
to 10 per cent, per mile, and need not be taken into account at all for only 
one station. No slipping of the rope in the groove ever occurs with a proper 
fiUign. The pedestals for the two-grooved wheels may be built of stone, 
iron or wood. It is usually cheaper to make a wooden frame butted to a 



242 



ROPE TRANSMISSION. 



masonry foundation extending below reach of frost. The frame should be 
braced from each side so as to maintain the wheel in a vertical plane ; end 
bracing is not required." 

Rope Connecting Rods, —The cuts, Fig. 139, show in plan and ele- 
vation, a system of rope connecting rods, giving a positive drive through long 
distances. As will be seen, there are upon each shaft three cranks, 120° apart. 



/J 



a 



u 




Fig. 139. — Wire Rope Connecting Rod. 



and each having a stub end. Each pair of stub ends is connected by tightly 
strained wire, of course, of equal length. When the axles revolve in the 
direction shown by the arrows, and when they are in the position shown in 
the cuts, the rope D will be in tension, E will be neither sFack nor taut, 
and F will be slack. This arrangement may be driven at slow or fast speed, 
thus giving an advantage over the wire rope in its ability to be run slow ; 
while its motion is as positive as that with rigid connecting rods. 



CHAPTER XVII. 



FRICTION AND LUBRICATION. 



Friction — Function of Lubricant — Hot Bearings — Lubricants — Compounded Oils — Evaporation — 
Spontaneous Combustion — Purity — Action of Oils on Metals — Bearing Metals — Proportions 
of Bearings. 

Friction. — Friction among solids is of two kinds, rolling and sliding, 
governed by different laws. The laws of the friction of journals (which 
includes both solid and fluid friction), are quite different from the laws of 
friction of solids, as given in text-books. Fluid friction varies with the square 
of the velocity, is proportionate to the area of the rubbing surfaces, and 
probably independent of the pressure. A fluid lubricant forms a fluid cush- 
ion, separating the surfaces more or less perfectly* according to its viscosity. 
The same surface lubricated with a given material may, under light pressures, 
seem to be governed by the laws of fluid friction, while under heavy pressures, 
the lubricant being squeezed out from between the solid surfaces, the laws 
of friction of solids come into play. The ratio of frictional resistance to 
total pressure from sliding friction varies directly as the pressure. It is inde- 
pendent of the speed and area of the rubbing surfaces. The laws of solid 
friction differ with the character of the rubbing surfaces. The friction of 
fibrous materials is increased by increased extent of surface and time of con- 
tact, and is diminished by pressure and speed. With wood, metal and stone 
(within the limit of abrasion), it varies only with the pressure, being inde- 
pendent of the extent of surface, contact and velocity. This limit of abra- 
sion is determined by the hardness of the softer of the two materials. Fric- 
tion is greatest with soft materials, and least with hard ones. The friction 
of lubricated surfaces is determined by the lubricant rather than by the 
solids. 

With rotating journals, friction is greater when the journals or bearings are 
not round, than when they are truly cylindrical ; greater when they are short 
than when long ; greater when there is much wear than when there is little ; 
greater when the surfaces are not finely finished than when they are of per- 
fect surface ; greater when improperly lubricated than when duly supplied 
with a fit lubricant ; greater at high speed and pressure than at slow. 

Bearing surface must be given by length rather than by diameter. It is 
the weight, per square inch of longitudinal section that determines the heating 
and friction. Bearings cannot run cool unless the minute high places on 
them are either removed or reduced, and the low places are filled up with 
some sort of unguent. If the caps of journal boxes are left too loose, the 



244 FRICTION AND LUBRICATION. 

journal will wabble, and if screwed down too tight, the lubricant will burn 
out and the bearing becontie ruined. 

Function of Lubricant. — The function of a lubricant is to provide 
rollers by which the movements of one surface upon another are rendered 
easier, besides which it distributes the pressure, making the journal press upon 
the bearings upon nearly all points of the semi-circumference, if its axis is 
horizontal, instead of upon a few points only. Of course, the diameter of a 
journal is slightly less than that of the box it runs in. The shaft being smaller 
than the box would touch at only one point, if it was not for the lubricant 
which fills the annulus between the two surfaces and distributes the pressure. 
The proper time to oil a box is a long while before it gets hot. Every time 
that you heat a box you are wasting power and destroying your bearing 
surfaces. 

The amount of tension on the belts very seriously affects the quantity 
of power required to drive a machine. In spinning threads, it has been 
found that if the amount of tension on the bands is increased from two 
pounds to four, the power would be increased 31 per cent., six pounds, 59 
per cent.; eight pounds increased 97 per cent. Some people seem to think 
that oil is simply to stop squeaking and to make things run easier; and 
because oil is necessary that it shows that machines are imperfectly made. 
Consequently the oil bill seems to be paid less cheerfully than any other 
about the establishment. Many a manufacturer in endeavoring to save a 
few gallons of oil loses several tons of coal. The axial pressure is stated 
by Radinger to be three times as great with pulleys as with gears. 

Hot Bearings. — It has long been known that sulphur cools a hot bear- 
ing, but the reason why is doubtful. Von Heeren states that the fine metal 
dust formed when a journal runs hot, and which strongly acts upon both 
journal and bearing, forms a sulphide with the sulphur. This compound, 
which grows soft and greasy, does not cause any appreciable amount of fric- 
tion. Sulphur and grease, in combination, are in regular use on board the 
steamers of the North German Lloyds. Oil should not be poured on heated 
journals. This is wasteful, and water is a better cooler. Graphite in oil is of 
use to prevent as well as to cool hot journals. Heating of the bearings may 
be from want of truth in the bearings themselves, or from their running 
dry. To see whether a shaft is true, hold a point steadily against it. 

Lubricants. — The value of a lubricant simply as a lubricant is indepen- 
dent of its cost. The heat of friction has several ill effects ; it reduces the 
viscosity of the lubricants, making them squeeze out at high pressure ; it 
cracks, breaks and destroys the surface of contact ; may ignite the lubricant, 
thus softening and weakening the abrading metals and causing liability to 
combustion, and it may weld the journals in their bearings. Lubrication is 
intended to reduce friction and prevent the development of heat. An effi- 
cient lubricator should have enough " body " to keep it from being squeezed 
out, but as far as is consistent with the former the sum of the two frictions, 
solid and fluid frictions, should be small. It should have high capacity for 
receiving, transmitting and storing heat, and for carrying it away. It should 
neither decompose nor change in composition, either in exposure to the air 



HOT BEARINGS—LUBRICANTS. 245 

or in use. It should be free from acid or from any liability to injure mate- 
rials with which it may come in contact. It should evaporate or decompose 
at a very high temperature and solidify at a low one. It should be especially 
adapted to the speed or pressure at which it is used, and be free from grit and 
all foreign matter. The character of lubricants used should vary with the 
surfaces rubbing together, with the speed they run, with the pressure. Sperm 
oil is one of the very best known lubricants, but high in price. Lard oil is 
more used ; it is cheaper and not so good. Some oils reduce friction well, 
but do not wear well, or cannot be kept on the journals. Linseed oils and 
the drying oils gum. Tallow is apt to contain acids or to form them. Some 
lubricants congeal at low temperatures ; others cannot be used in steam cyl- 
inders because they decompose or evaporate. 

One of the best lubricants is graphite, also called plumbago and blacklead. 
When of proper fineness and purity, it packs itself between the projections, 
fining them up level. Being a solid, it is especially adapted to those places 
where there is great pressure, which would likely squeeze out any liquid 
lubricant ; and being unalterable by heat, it is less likely to be affected than 
oils, which are unstable in their compositions. Being unaffected by cold, it 
never gives any trouble by gumming or thickening. But it must be perfectly 
pure, tough, free from grit, and of the proper sized particles. The best of 
which the writer has any knowledge is made by the Dixon Crucible Company, 
Jersey City, N. J. It is put up in several shapes and in several grades. For 
millstone spindles, the grade called " perfect lubricator " should be used. For 
vertical smutters, separators, and brush machines, the same grade of graphite 
should be used as for heavy machinery, except that it should be prepared m oil 
and not in grease, and so prepared as to remain in suspension in the oil. Thus 
prepared, the makers claim that it will feed freely through an ordinary oil- 
can. For engine slides, there is difficulty in feeding anything but the 
very finest oils, and graphite as yet has not been successfully used for them. 
F^or wooden bearings graphite is especially to be recommended. 

At low temperature the viscosity of kerosene is equal to that of lubricating 
oils at the average temperature of bearings in gerieral use ; hence we find 
kerosene of use in extremely cold situations, as under great cold its fluidity 
is enough to cause it to enter the bearings. 

A person wrote to the American Machinist : "I desire to know the value 
of castor-oil for machinery. Is there any acid in it ? If you have any arti- 
cles upon castor-oil as a lubricant, please send me the same, in order that I 
may obtain some light." The reply was as follows : " Castor-oil has an 
exceedingly heavy body, and at a temperature of 59° Fahrenheit has a spe- 
cific gravity of .9667, while the best bleached winter sperm has a specific 
gravity of .8813, and lard winter a specific gravity of .9175. Castor-oil is an 
exceedingly durable lubricator. During some tests which were made on a 
testing machine belonging to the Lake Shore and Michigan Southern Railway, 
fifty drops of the different oils tested were used at one application, and the 
machine, which has a journal corresponding to the size of a car journal and 
subjected to an equivalent pressure, was driven at a speed representing thirty- 
five miles per hour, until the temperature shown by the thermometer rose 



246 



FRICTION AND LUBRICATION. 



from 60° to 200° Fahrenheit. The following is a summary of the test which 
shows the endurance of the oils tested : 



Castor, . 


12,946 rev. 


WestVa., 


. 7,915 rev 


Paraffine, 


11,685 " 


Sperm, 


• 7.912 " 


Mecca (black), . 


9,982 " 


Tallow, 


• 7.794 " 


Neatsfoot, 


8,277 " 


Lard, . 


■ 7.377 " 



These tests have been criticised, but as the railroad company continued 
to use the cheaper oils it may be taken as evidence that they are at least 
approximately correct. There are some objections to the use of castor-oil 
for general lubrication, the most prominent of which is its cost. 

Fully one-half of the oil used in mills for lubrication is wasted. The 
author knows of a manufacturing establishment where the hangers of their 
line shafting work perfectly with only thirty-four drops of oil each per week. 
To determine the viscosity and rate of gumming of oils, place a drop of each 
sample on the top of an inclined plane, and note the time required to run 
down. Of the ungumming oils, the least viscous will reach the bottom first. 
Of the gumming oils, the quickest drying are the slowest to reach the bottom. 
The smaller the mill, the greater the advantage in using good lubricants. In 
large mills the cost of a horse-power averages only $50 per year, but for 
small powers it runs to four times that ; hence a lubricant saving 5 per cent, 
would save $500 per year where 100 horse-powers are used. The amount of 
oil used would run only from 40 to 100 gallons. It would be cheaper for the 
consumer to pay $5 or even %\o per gallon for a good article than to accept 
a poor one as a gift. 

There is one thing that is not generally taken into consideration, and 
that is, that different sizes of bearings require different lubricants, and that 
different pressures also require different means of lubrication. Some oils are 
penetrating, some are viscous ; some readily enter between the bearing sur- 
faces, some do not ; some are easily forced out from between the surfaces by 
excess of pressure, some are not. Some oils are good for high speeds, some 
for slow. Those that are good for high speeds are not good for the same 
bearings at slow speeds. I might say in reply to a special query : " for steel 
surfaces lubricated with the best sperm oil, and moving slowly, 1,200 pounds 
per square inch of bearing surfaces permissible ; " but if the conditions were 
different, the reply would be different to correspond. If the surfaces were 
rougher and softer, if the oil was of a poorer quality, or if the speed was 
higher, the pressure admissible would have to be reduced, and if the pressure 
was unchangeable and the bearings were less perfect, the speed would have 
to be reduced to prevent heating. If the gross pressure, and the material of 
the bearing, or the speed could not be changed, then the bearing would have 
to be lengthened, so as to make the pressure per square inch much less. 

So eminent an authority as Professor Sweet says in reference to the ques- 
tion of economy by reduction of friction, that of two systems — one offering 
a saving of 10 per cent, by reduction of friction and the other of 20 per 
cent, in the use of steam, he would take that which led to a saving in friction, 
which of necessity implies saving in maintenance, attendance, repairs, delays, 
etc. This loss by attendance, repairs and delays is greater in small engines 



COMPOUNDED OILS. 247 

than in large. To get economy in friction there should be generous wearing 
surfaces, well fitted and properly lubricated, and the engine should be in 
absolute alignment, We often find shafts which are set in perfect line and 
remain so when at rest, but which are deflected by the strains put upon them 
while at work. 

Owing to the smaller cost of the lighter volatile oils, they have been exten- 
sively used in mills for lubricating, instead of the better but higher priced 
oils ; but the fact that the heavier and more expensive oils are really the 
cheapest lubricants is now more generally recognized by mill owners. The 
discovery of this fact, based on statistical tables of the relative quantities of 
cloth made and the amount of lubricant used during its manufacture was 
brought about in a very curious way, through the instrumentality of the 
Boston Manufacturers' Mutual Insurance Company. The attention of the 
insurance company was drawn to the greater liability of light oils to take fire 
through spontaneous combustion and friction, or producing highly inflam- 
mable vapors, the ignition of which cause dangerous fires, resulting in loss of 
life and property. Edward Atkinson, president of the company, in August, 
1878, collected data from mill owners showing the relative amount of lubri- 
cants used to cloth produced. The average amount for 56 mills was from 
1.03 to 2.88 gallons of oil for every 1,000 pounds of cloth from ^^ yarn. In 
1880 similar data were collected from mills insured by the company and 
using heavier and safer oils ; and there was found to be ^;i per cent, saving 
in favor of the safer and better lubricants, representing $180,000 gain by the 
seemingly more expensive lubricants. Now, if from this we take 40 per cent, 
for the reduction in price in oils between the years 1878 and 1880, we have 
$100,000 absolute profit from the use of the better oils. These figures are 
not hypothetical, but are the results of carefully collected data from mills 
representing over 4,000,000 spindles. This principle of economy is available 
for all classes of mills. 

Compounded Oils. — A very objectionable class of oils consists of 
mixtures of light and heavy oils, residues from still bottoms, having light oils 
added to them to give a consistency and deceiving gravity, but under the 
heat of steady work the light oils are volatilized and the lubricating power of 
the oil lessened, while the fire risk is increased. 

The flashing point of lubricants is important to know, because the danger 
of fire from the use of any oil is not determined from the point at which the 
oil itself ignites, but by the lower temperature at which the vapor that rises 
from the oil bursts into flames. Thus, a smutter employing an oil which 
gives off a vapor igniting at a temperature of 140° F., would be in danger, 
because the temperature of 140° would be likely to be reached if the oil 
supply ran at all low, or the tension of the bands were increased by over- 
lacing, and the vapor which extends as far as the fine dust, given off the 
machine would be liable to inflame and set fire to the dust, which would in 
turn communicate the flames to the whole mill. Outside of the question of 
fire risk, if the lubricant gives off at the running temperature, a volatile vapor, 
and yet does not permit it to inflame, there is a certain amount of oil that has 
been paid for, which does no work in lubrication. 



248 FRICTION AND LUBRICATION. 

Evaporation. — Mineral oils by evaporation lose at 140 from one to 
thirty per cent. Animal oils gain slightly in weight at that time owing to 
oxidation. 

Spontaneous Cumbustion. — To estimate the tendency to sponta- 
neous combustion, take a given weight of cotton wool, saturate it wholly or 
slightly with the oil in question, put it in a confined place and note the ris- 
ing temperature in twenty-four hours. 

Purity. — To know the freedom of a lubricant from acid, observe its 
effect upon a cleaned copper plate. 

Action of Oils on Metals. — At a meeting of the British Association, 
Prof. William Henry Watson read a pajjer upon the action of certain 
oils on metals, which is a valuable contribution to the literature relating to 
lubricants. At the Plymouth meeting of this association he brought forward 
the results of some experiments, showing the action of various oils on copper, 
and the conclusions arrived at were briefly these: i. That of the whole of 
the oils used, viz., linseed, olive, colza, almond, seal, sperm, castor, neatsfoot, 
sesame and paraffine, the samples of paraffine and castor-oils had the least 
action, and that sperm and seal oils were next in order of inaction. 2. That 
the appearance of the paraffine and the copper were not changed after sev- 
enty-seven days' exposure. 3. That different oils produce compounds with 
copper varying in color, or in depth of color, and, consequently, rendering 
comparative determinations of their action on that metal, from mere observa- 
tions of their appearances, impossible. He was disposed to conclude that 
these experiments would indicate the relative action of the oils on other 
metals, simply expecting that the extent of action would vary throughout, but 
that the variations would be proportionate between the oils. Since the pub- 
lication of these results, however, an interesting paper appeared in the Phar- 
maceutical Journal, "On the Action of Paraffine Oils on Metals," by Dr. S. 
Macadam. He comes to the same conclusion as Professor Watson with 
regard to their action on copper, but, referring to iron, " it is slightly affected 
by paraffine oil, and on ten days' contact the oil becomes deeper in color and 
throws down a fine ferruginous sediment." Owing to this. Professor Watson 
lately made experiments on the action of the same oils as those previously 
used on copper and on iron, and the results, which are the subject of this 
communication, are interesting, as. showing that there is no relation between 
the action of an oil on copper and the action of that oil on iron ; that, in fact, 
in several instances, those oils which act largely on iron, act slightly on cop- 
per, while those which act largely on copper act little on iron. Of course, 
the actual extent of action of the same oil (with the exception of paraffine) is 
greater on copper than on iron. In addition to the oils used in his experi- 
ments on copper, he also used a sample of lard oil, and a special lubricating 
oil. The following observations were made after twenty-four days' exposure : 
I. Neatsfoot. — Considerable brown irregular deposit on metal. The oil 
slightly more brown than when first exposed. 2. Colza. — A slight brown 
substance suspended in the oil, which is now of a reddish-brown color. A 
few irregular markings on the metal. 3. Sperm. — A slight brown deposit 
with irregular markings on the metal. Oil of a dark brown color. 4. Lard. — 



ACTION OF OILS— BEARING METALS. 



249 



Reddish brown, with slight brown deposit on metal. 5. Olive. — Clear and 
bleached by exposure to the light and air. The appearance of metal same as 
when first immersed. 6. Seal. — A few irregular markings on metal. The oil 
free from deposit, but of a bright red, clear color. 7. Linseed. — Bright deep 
yellow. Oil bleached and free from deposit. 8. Almond. — Metal bright. Oil 
bleached and free from deposit. 9. Castor. — Oil considerably more colored 
(brown) than when first exposed. Metal bright. 10. Paraffine. — Oil bright 
yellow and contains a little brown deposit. The upper surface of the metal, 
on being removed, is found to have a resinous deposit on it. 11. Special Lu- 
bricating. — Metal bright. Appearance of oil not perceptibly changed. The 
samples were then chemically examined, and the amounts of iron found in 
them were as follows : 



Oils. 


Grains. 


Oils. 


Grains. 


Neatsfoot (English) . 


0.0875 


Seal 


. 0.0050 


Colza .... 


0.0800 


Castor 


. 0.0048 


Sperm .... 


0.0460 


Paraffine . 


0.0045 


Lard .... 


0.0250 


Almond . 


0.0040 


Olive .... 


0.0062 


Special lubricating . 


. 0.0018 


Linseed .... 


0.0050 







For comparison, the following are the results obtained of the action of 
these oils on copper, as previously communicated, after exposure of ten days : 



Oils. 
Neatsfoot 
Colza 
Sperm 
Olive 



Grains. 


Oils. 


O.I 100 


Linseed 


0.0170 


Seal 


0.0030 


Paraffine 


0.2200 


Almond 



Grains. 
0.3000 
0.0486 
0.0015 
0.1030 



Owing to the length of exposure being different in the two series, we can- 
not fix on the actual differences in the rate of action of any of the oils on the 
two metals. However, it is shown that almond oil, which acted largely on 
copper, acts very lightly on iron ; in fact, with the exception of the paraffine 
and special lubricating oil (a mineral preparation), it acted less than any of 
the other oils on iron. The same is shown, as already mentioned, as to the 
action of various other oils ; thus, while sperm oil acts slightly on copper, it 
acts considerably, compared with the others, on iron. Linseed, seal, castor, 
almond and paraffine, may be bracketed as having about the same and very 
little action on iron, while linseed, olive, neatsfoot, almond and seal have the 
greatest action on copper. 

Bearing Metals. — All persons are not of the opinion that phosphor 
bronze is the best. A large rolling-mill owner says that he prefers first-class 
copper and tin for his work. He has large experience, and is a close ob- 
server, and says that the heat of the rolls acts badly on the phosphor bronze, 
besides, he suggests that copper and tin bearing is cheaper. Even i-eal bab- 
bitt-metal is not always found to be of such great value, as it gets particles of 
grit imbedded into it, and thus "laps" a place in the shaft and reduces the 
diameter. There are numbers of instances of that, and in such a case the 
place where the bearing is cannot be changed. Some claim that it takes 
more power to run it than cast iron. Brass or babbitt-metal has this advan- 
tage over iron for bearings of wrought-iron journals; outside of its lesser 



250 FRICTION AND LUBRICATION. 

coefficient of friction, it conducts the heat away from the journal more 
rapidly than cast iron does. Wherever the pressure exceeds 125 pounds per 
square inch, projected area, brass or soft metal bearings should be used. 
Each class of work should have a bearing material to suit it. In choosing, 
be governed by the experience of others under exactly similar circumstances; 
and by records of tests made to show just what qualities each material has. 

Proportions of Bearings. — Bearings should in most cases be long, 
to distribute the pressure and wear ; and the journals should be of as small 
diameter as stiffness will allow, to lessen the leverage of the resistance. 



^*^ 



CHAPTER XVIII. 



BACKLASH AND SIDE PULL. 



Backlash — Coil Spring — Side Pull. 

Backlash.. — Backlash is largely caused by the fact that the crank acts 
with greatest force when at right angles to the piston rod, and with least 
when on the dead centres. Thus there are two points in each rotation when 
the crank leads the burrs, and two when it is led by them. Making the fly- 
wheel very large and heavy remedies the defect, to a certain degree, because 
a body resists change of speed in the direction of its motion just as much as 
in the opposite direction. Having fly-wheels of great diameter should drive 
from its rim, for the purpose of giving the machinery leverage over the 
engine has no such result ; besides which, the cost of the motor is increased. 

One cause of backlash is the elasticity of the belts. A pair of wheels 
not properly mated at their pitch lines, and not pitched and trimmed prop- 
erly, will always backlash. Backlash is often caused by wheels being bored 
out of centre. It is said by some that one way of stopping backlash is to 
make the rim of the fly-wheel lead the skirt of the stone by ^ ; thus, if 
the skirt travels 2,400 feet ])er minute, the rim of the fly-wheel should 
travel 3,200. This is entirely wrong. The motion indicator will show at any 
time whether the burrs are running too fast or not, and whether there is back- 
lash enough to interfere with their proper running. 

Coil Spring. — The evil of backlash is successfully combated by the 
Eureka Coil Spring. This is made of three plates of cast spring steel, 
riveted together at the inner or hook end. The lengths of the springs 
are so proportioned that the strain on the outside, which is the thickest 
plate, is tensile, while that on the inner plates is prehensile. Its length is 
seven and a half feet. Fig. 140 shows the spring in its casing, applied below 
the pinion, which is loose on the spindle, and rests on the centre hub of the 
spring, which is keyed fast to the spindle. The two opposite arms of the 
pinion fit into the corresponding edges of the casing, which is fitted to play 
easily and freely on the head, to which the inner end of the spring is fastened, 
as is shown at A, Fig. 141. Its outer end is fastened to the casing by a bolt, 
as shown at W, Fig. 140. Thus the connection between the spindle and the 
pinion is elastic. When the gearing is spur and there is not enough space on 
the spindle below the pinion, it is advisable to raise the crown wheel and pin- 
ions enough to let the spring go underneath. The pinion can thus be raised 
out of gear in a few moments, while the spring remains keyed fast to the 

17 



252 



BACKLASH AND SIDE PULL. 



spindle. The automatic stop prevents the spring from being injured by 
backing the engine. 

There is an oil cup which is filled with wick and placed on the spindle 
above the pinion when the spring is applied below, so as to lubricate the pin- 
ion, spindle and spring. The hub, or sleeve, ought to be faced off flush with 
the arms of the pinion ; but if it extends beyond on the side where the spring 
is to be applied, the casing must be made accordingly. The key that is between 
the spindle and sleeve must be taken out in every case, for the vibration 
must be between the spindle and sleeve, and not between the sleeve and pin- 
ion (except when especially designed, and the sleeve is provided with a flange 
for the pinion to rest on). Where pinions have no sleeve, as shown in Fig. 
140, the millwright must be governed accordingly. Square spindles require 
special treatment. 

Fig. 142 shows the spring applied above the pinion. This is generally 
done when there is not enough space on the spindle below the pinion, or 
when the lower side of a bevel pinion is too small, so that the casing of the 
spring, which is sixteen inches diameter, would come in the way of the driv- 





FlG. 140. 



Fig. 141. 




Fig. 142. 



ing wheel. It is best to have a key with a large head, which can be lifted 
loose with a light bar (a feather can only be used when the pinion has a 
sleeve), and thus raise the spring with the pinion. It requires a wrought-iron 
collar to go below the pinion when the spring is applied above, but no extra 
oil cup, as the hub of the spring has a recess for oil. Springs ought to be 
applied on the spindles of each pair of burrs ; thus, each burr works inde- 
pendently, and is not affected by the others, nor is it subject to any irregu- 
larity of the cogs ; and when the machinery is driven both by steam and 
water, a large spring should also be applied at the connection, so that each 
motor (engine and water-wheel) applies its power independently, and neither 
affects or is affected by the constant irregularities of the two forces. When 
applying this spring, be careful not to drive the key too hard so as to wedge 
the hub against the casing and lock it. Be sure that the casing plays freely on 
the hub, and the pinion free on the spindle. Chip the driving side of the 
jaws of the casing so they have equal bearing and hold paper on both arms ; 
mark the arms and jaws so that they go together the same way every time. 
The arms of the pinion must not rest on the bottom of the gap between the 
driving jaws. The device can be applied in one or two hours. 

Side Pull. — Two objections which have been made to the use of belts 
in driving millstones are the side pull on spindles and variable tension. The 



COIL SPRING—SIDE PULL. 



253 



equilibrium driving pulley, made by John A. Hafner, Pittsburg, Pa., has 
been devised to overcome these objections. In Fig. 143 is shown the im- 
proved form of this pulley, of which the following is a description: 

A A, is the hub of the driving pulley, the arms being curved from the top 
of the hub to the centre of the rim in order to bring the centre of the rim on 
a line with the centre of the hub, so that the pull of the belt will be squarely 
on the bearing. B B are bushings set in the bridge-tree to form a bearing 
for the hub. C is the mill spindle resting on the step G. The bore of the 
hub A is larger than the spindle, the latter having no connection with the 
pulley except through the equalizing driver E and Hafner's Eureka Coil 
Spring D. Oil is fed in through an ordinary oil cup and pipe J, the pulley 
hub resting on the collar F, and the oil being prevented from leaking out by 




Fig. 143.— Hafner's Equilibrium Driving Pulley. 



the packing K, in the groove in step G. The spindle is raised and lowered 
by an ordinary lighter screw acting through the compound levers H h, by 
which all tendency to throw the step sideways or out of tram is avoided. 
The quantity of oil in the bearing is indicated by the glass tube J. Thus the 
side pull on the spindle is prevented by the hub of the pulley A revolving in 
the bearing B, and receiving the strain of the belt instead of the spindle C. 
Variable tension of the belt is also counteracted by the elasticity of the coil 
spring D. The spindle, therefore, free from all outside influences, simply 
rotates on its pivot, and a perfect motion is secured. To tram the pulley 
with the spindle, tighten the belt the same as when driving the stone ; fasten 
a tram-staff on the spindle above the spring. The staff is curved down so as 
to reach the rim of the pulley, which is adjusted by set-screws on followers. 



CHAPTER XIX. 

GRAIN CLEANING. 

Cleaning — Ending — Screens — Grading and Separation — Hungarian System of Cleaning — Cockle — 
Cockle Separation — Oat Separation — Grader and Dustless Separator— Smutter and Separator 
—Wheat Brush. 

Cleaning. — The object of cleaning is fourfold : First, to extract from the 
wheat as thoroughly as possible all dust, dirt, clay, stones, and foreign sub- 
stances which would tend to impair the quality of the flour, together with the 
beard and crease dirt in the berry itself ; second, to extract any light, shriv- 
eled, or soft berries that are among the sound ones ; third, to remove any 
grass, cockle, oats, and other seeds, clean or otherwise, that it may contain; 
fourth, to insure that it is perfectly dry. 

Cleaning ordinary grain may be divided into the operations of wind 
separation, scouring, magnet separation, and brushing. In some mills grad- 
ing and ending are employed ; and where the grain is musty or damp it 
requires drying and sweetening before any other operation. Musty grain 
may be made sweet and sound by immersing in boiling water. All the de- 
cayed grains swim on the surface. The good heavy grain should then be 
dried. Heated wheats may have their musty or " ship " smell removed by 
the use of sulphur and sal-ammoniac on a clear fire, allowing the fumes to 
pass through the grain. 

The wheat-cleaning machines should be placed so that they can be easily 
reached and carefully looked after by the miller without extra trouble or 
going up to the top of the mill or the farthest corner of the basement. Clean- 
ing machinery is often stuck in some dark corner, simply because it makes a 
dust. Where the machines are in the way elsewhere, cleaning and grading 
can be done in an outside building or in a good light basement, thus giving 
more room for the bolting and purifying operations. Some seasons' wheat is 
very dirty; some localities furnish dirtier wheat than others ; and some kinds 
of wheat are easier cleaned than others. Wheat v/ill be more than ordinarily 
foul to have more than one pound of dirt per bushel of sixty pounds (by 
dirt meaning foul stuff of all kinds). Good wheat should not have half a 
pound of dirt per bushel. In California and Oregon small stones in the 
wheat are troublesome. 

Since the advent of the wire-binder, attention has been called to the pres- 
ence in wheat of pieces of wire, etc., and the et cetera is found to be small 
nails, tacks, bits of sheet iron, pieces of elevator cups, rivets, pieces of the 
threshing machine cylinder or teeth, pins, needles, and in some localities 
" black gravel," which is iron ore — altogether quite a miniature junk-shop. A 



CLEANING. 



255 



thousand bushels of wheat were run through the spout in the celebrated 
Washburn B Mill, Minneapolis, and the magnets took out seventy-three 
pieces of wire and seventy-one pieces of other metallic substances, consist- 
ing of three tacks, two ends of cut nails, one end of horseshoe nail, and 
sixty-five small bits of wrought iron and sheet iron, varying in size from one- 
eighth to a quarter inch, in irregular shapes, many of them appearing to be 
scales or fragments broken from badly worn machinery. Discriminations 
against wire-bound wheat are hardly practicable, and yet if they do not strike 
fire the tiny bits of wire are flattened out by the burrs and become tiny saws. 
The wire-binder is responsible for two-thirds of the iron found in the wheat. 
It is a mistake to suppose that magnets can take out other than iron or steel 
particles. The magnets should follow the wind separation, as there is then 
less liability of clogging in the spouts. Magnets are best put in spouts where 
currents of air work in the wheat. Fig. 144 shows the magnets arranged in 
parallel rows, and Fig. 145 arranged in a better manner, obliquely in the' 
spout. 




Fig. 144. 



Mill Magnets. 



Fig. 145. 



As magnet makers we can recommend the Harris Safe Works (S. H. 
Harris, proprietor), Chicago, 111. 

There are three principal modes of separating light grains and wheat 
from heavy and foreign seeds and other impurities. These are the sieve, 
blower, and rubbing. Sieving or screening takes advantage of the different 
shapes and sizes of the bodies to be separated. Light grain, dust and chaff 
are taken out by suction or blast fans. The oat grain is got out by taking 
advantage of its elongated form. The light or blasted kernels and the straws 
or chaff are removed by an aspirator. Friction should remove the hairy 
fibres or fuzz from the end of the berry and all dirt adhering to the grain. 
It should leave the grain smooth and polished, without breaking the bran- 
Any cleaner that breaks wheat causes a waste. There is no use in saying 
that wheat cannot be cleaned so that there shall be no fuzz on the end of the 
grain, because this not only can be done, but is done every day in many 



256 GRAIN CLEANING. 

mills. The fact that it is not done in nine mills out of ten only shows that 
there is room for improvement there. 

Where winter wheat alone is to be cleaned fewer sieves can be used in 
separation, and there being no oats to take out, a larger hole can be used in 
the sieve, thus giving greater capacity. Placing the separator on the grinding 
floor (especially for spring wheat) has the advantage that it is under the eye 
of the miller, who can give it the necessary attention without running up and 
down stairs. Wheat cleaned before shipping not only transports and keeps 
better, but brings a higher price than that which has not been cleaned. 
Separation before storage prevents choking when feeding to the cleaning 
machine. Wheat sieves will clean rye also. While oats can be cleaned on 
corn sieves, this plan is not recommended, being too slow to suit shippers. 
Oats are very difficult to remove from spring wheat, requiring small holes in 
the sieves and an extra number of sieves. Adding a set of sieves with holes 
especially adapted to remove oats from wheat will, while taking out all the 
oats, reduce the capacity of the machine fully one-half. The capacity of a 
separating machine is about one-fourth to one-third less for corn or barley 
than for wheat. The scouring machine is not intended to remove straw, 
chaff, stones or nails. It should break all the smut balls and not break the 
wheat. A screen i8 feet long, 30 inches in diameter, and making 30 revo- 
lutions per minute, with a fall of 9 inches, ought to clean 40 bushels per 
hour. To take out cheat, long narrow meshes are requisite ; for cockle, 
small square meshes will answer. It is, however, much better to buy one of 
the excellent special scouring and brushing machines than to make one. 

It is surprising how much more attention is paid to the subject of cleaning 
than formerly. Millers are commencing to realize that the earlier they take 
out the dirt, and the more dirt they take out, and the more careful they 
take it out, the better chance there will be for white flour, other things being 
equal. In one way the cleaning may be improved, in large mills at any rate. 
The Simpson & Gault Mfg. Co. states that when several machines are worked 
together (as a separator, smutter and brush), the dirt taken out will weigh 
from 3,000 to 5,000 pounds per 1,000 bushels, depending upon the quality 
of the wheat, the amount of cleaning it gets in threshing, etc. This seems 
excessive. " Little and often " .is a good motto for cleaning ; that is, if there 
is a certain amount of work to be done, that it should be done by constant 
rather than by sudden action. 

A custom mill should be so constructed that the grain can be cleaned be- 
fore it is weighed. The miller knows what he is getting. Clean every grist, 
then weigh it, and book it. Grists range from one to ten pounds of dirt to 
the bushel. One authority states that he has cleaned as many as fifteen 
pounds out of a few grists. Such grists are made up largely of screenings, 
and are "made to sell." 

Millers should try to impress upon farmers that it pays them to deliver 
clean wheat, and they can emphasize what they say in this connection by show- 
ing them the result of carelessness upon the wheat trade of our Pacific coast. 
In some districts there is trouble with what is called the Texas pea, about one- 
third larger than the ordinary cockle, and almost impossible to separate. 



ENDING— SCREENS. 357 

One of the greatest nuisances in Pennsylvania is the presence of garlic, 
which gums or clogs up the burrs, requiring them to be frequently scrubbed 
or to have a special dress. Sometimes the nuisance is lessened by the rolling 
cockle screen with cup-shaped indentations ; but in any case, the presence 
of garlic in any great quantities is the cause of annoyance and loss in burr 
mills. Strange to say, in some sections, as the interior of Pennsylvania, the 
garlicky wheat that the millers are troubled with comes from farmers who are 
wealthy and never sell until midsummer. Some kinds of wheat, as Michigan, 
are best treated without scouring, the brush taking care of it well enough. 
A great many mills have no . room nor power to run both a smutter and a 
brush machine. For this class the combined smut and brush machine is 
recommended. 

There are some machines employed in the cleaning of grain that ought to 
be entered as disintegrators, such and so damaging is their action upon the 
grain. The smut machine that breaks all the smut balls and does not break ' 
the wheat is the one the miller should buy. 

Cockle is most plentiful in Wisconsin, Minnesota, Dakota, Northern Iowa 
and Nebraska. The offal in cleaning is about two pounds per bushel of 
cockle and similarly-shaped seeds. Where there is not a special cockle- 
extracting machine, cockle is more readily separated after being reduced in 
size by the smutter. 

Ending. — It is especially claimed for ending stones that they break no 
wheat and take little power. Before ending, the wheat should be graded in 
three different lengths by sieves or screens with a gentle end motion. For 
ending, a good quality of sandstone is used. The stones should be put up for 
work like ordinary burrs, the upper one running. The dress of the runner 
should be such as to draw the grain in rather than to throw it out. A rigid 
runner should be used, and the faces kept apart at such a distance that the 
grain is not touched unless revolving on end. They should be taken up and 
dressed every three days. The bed-stone should have no furrows, but a good 
deal of bosom, say 30 inches in a 5-foot stone. After the ending stone the 
wheat is sent to an ending reel. The refuse (points and a little flour and bran) 
goes to another reel. The flour is dark and the bran very poor. The points 
are ground with the bran into very low grade flour. 

Screens. — A screen 18 feet long, 30 inches in diameter, and making 30 
revolutions per minute, should clean 40 bushels of wheat per hour. The 
form of the meshes should be chosen with reference to the nature of the offal 
to be taken out. Cockle needs small square meshes and cheat long narrow 
meshes. A shaking screen is more liable to clog up than a rolling one. 
Whatever be the material employed it should be evenly punched without burr 
or bulge. It is by far the best to buy these screens ready punched, but in 
places where this cannot be done in time the metal can be punched with a 
steel punch upon a large cake of lead, or upon the end of a large block of 
hard wood, this last needing to be cut off from time to time, as it gets too 
much indented, and the lead needing to be hammered smooth. If it is pos- 
sible to have two rolling screens they will work better than one, because the 
second screen may have smaller meshes than the first, and the small plump 



258 



GRAIN CLEANING. 



grains of wheat which may have passed the meshes of the first will be stopped 
by the second. 

There are two principal types of screens, those woven of wire and those 




iiifiif 

1 1 1 1 1 1 1 1 1 II 
I f llli li llllll lill 

I 1 1 I IN 1 1 1 \ i 

! I li I it 

! II II I I I I i 




II 


11 


li 




iiii 


1 

ill 

:' li i !" It 


11 ' li 
1 ' 1 

\ \ 

1 || 


;i 

' '> \ 
1 1' 


in 


•m ' 


ill 



KiG. 146. 



made of perforated plates. The first have naturally greater screening capa- 
city (as far as mere separation according to size is concerned) than the 
second class ; but in the second class there is a greater adaptability to sep- 



SCREENS. 



259 



aration, according to shape ; and this, added to their superior durability and 
their cheapness, makes them the most common and popular in this country. 



No. 



SV« 



3 



8V2 








No. 



472 



6 



8 





Fig. 147. 



The cut shows a number of styles of screens, in their natural sizes. It will 
be noticed that there is one style which is made of rods or bars running 



260 



GRAIN CLEANING. 



lengthwise and wattled together by wires, so as to leave very long unob- 
structed spaces. Fig. 146 and part of Fig. 147 show a style of machine very 




Fig. 148. 



common abroad, especially with Swiss houses. It has the merit of having 
openings more nearly approximating to round holes than the ordinary square 



SCREENS. 



261 



mesh made in this country. The figures attached give the foreign numbers. 
Perforated screens, which are the rule in this country for mere grading to 




Fig. 149. 



size, have three principal shapes of holes — round, oblong and triangular — 
these varying in size, spacing and arrangement. Round and triangular holes 



2{i2 



GRAIN CLEANING. 



are generally arranged " staggering " — that is, the holes in one row alternate 
with those in another. Oblong perforations are generally arranged in paral- 




FlG. 150. 



lei rows. Referring to Fig. 148, Nos. 2 to 5 are employed for sieving and 
screening, grading middlings, bolting corn meal, etc., up to -^ of an inch 



SCREENS. 



263 



in diameter. No. 6 (yV-inch perforation), No. 7 (of ^-inch hole), and 
No. 8 (yV-inch), take out flax and all small seed. No. 9 {-i^ of an inch), 




Fig. 151. 



10, II (-gV inch), 12 and 13 (^ inch), are for cockle and flax seed. Of the 
perforations shown in Fig. 149, Nos. 25 (-^ inch), 26 {-^ inch), and 27 



264 GRAIN CLEANING. 

(f inch), are for oats and corn. Nos. 28 to 36 are little used in this 
country. In Fig. 150, Nos. 38 to 42 are for generally screening purposes; 
No. 44 is for scouring grain. Nos. 44 to 46 are used in scourers, pearl barley 
machines, hominy mills, etc. Nos. 47 and 48 are not now much used in 
America, although demanded abroad. For timothy, there is demanded ^- 
inch hole ; smutters take long slots, yV ^ if inch ; flax, -^-^ x g^ inch, with 
round ends ; oats, i x i^ inch, with round ends. Kiln floors for drying oats, 
etc., may have holes either round or -^-^ x^ inch, oblong, but should be ol 
No. 16 iron at least. Round holes, \ inch in diameter, answer for oats 
and corn. Elliptical perforations, i x f , answer for corn. For barley and 
flax, ^^ X f inch oblong holes, with round ends, are used. Wheat takes -^-^, 
\ and -jV inch round holes, f inch and \ inch round will answer for corn ; 
and the same shape, ^ x f inch, does for oats. Barley takes -^ inch round ; 
■^ inch round answers for cockle, and -^ inch round for cockle and flax. 
Some smutters take what is called lip style, the perforation being of H shape, 
and left projecting like a tongue. 

In Fig. 151 are shown several other styles. No. 14 (-^ inch round) is for 
buckwheat and flax; No. 15 [^ inch), the same; No. 15A (-^ inch), for 
wheat ; No. 16 is the same, but the rows run the other way across the sheet ; 
No. 17 (-jV inch) is for wheat; No. 18 (^ inch round), for wheat, used in 
separators, threshing machines, etc.; No. 19 (y^ inch), used for wheat and 
barley; No. 20 (-/^ inch), for barley and rye; No. 21 (f inch), for barley 
alone; Nos. 22 {^ inch) and 23 (^^ inch), for oats and barley; and the 
last one of the set i^\ inch round), for oats alone. The materials employed 
for these screens are plain and galvanized iron and zinc. This work must 
be done carefully, or the plates will be weakened and the holes rough. 
Harrington & Oglesby, of Chicago, are reliable people to deal with in this 
line. 

Grading and Separation. — Many riddles simply measure the grain 
passing through them, and select only the larger grains. Many small plump 
grains that measure less than the cockle pass through the riddles, while the 
larger grains of less weight and value pass on with the good wheat. The 
fanning mill with riddles is apt to run off with the heaviest wheat with the 
straw and tailings, when the crank is turned too fast, before it can pass 
through the meshes of the riddle. 

Grading is advisable before smutting or brushing. That which passes over 
the tail of the cockle separator will be best smutted and brushed by itself 
and reduced by itself if possible. The small berries should be scoured and 
brushed separately, because if the machine is set to scour or to brush the 
large grains it will not handle the small ones as perfectly, and if set close 
enough to work the small ones it will be too harsh for the large ones. If the 
wheat has tough, thick bran it will be well to give it a good scouring and one 
or two brushings ; but if it is tender the scourer may sometimes be dis- 
pensed with. 

There is nothing like careful and thorough separation; but it must be 
remembered that the machine or the method that will clean one kind of grain 
is not always the best for all other kinds, and indeed sometimes for any other 



GRADING AND SEPARATION— HUNGARIAN SYSTEM. 



265 



kind. And in cleaning different sizes and weights of grain the machine 
should be adjusted to the different kinds of work it has to do. Sometimes 
we find people complaining that they cannot clean barley or rye to their 
satisfaction ; but it would be a wonder if they could, because their machines 
or devices are of the crudest kind and kept in very bad order, if there is 
such a thing as bad order. 

Hungarian System of Cleaning, — The wheat is passed through 
two 15-feet reels, 3 feet diameter, running 28 revolutions. Each reel is 
covered with four sheets of wire ; two sheets of No. 14 at the head, to let 
the dust and small seeds through, and two of No. 6, to let the wheat and 
grain of^the same size fall to a hopper. Then comes scouring on two reels. 



■ Straw, Dirt, 
&c. 



14 


14 


6 


6 



Dust. 

Fig. 152. 

For a 24-run mill they are thus clothed : 



Wheat. 



14 


14 


12 


12 



Large Wheat. 



Scouring Dust. 



Fig. 153. 



Small Wheat. 



The scouring dust is sold for feed, perhaps, and the small wheat for poultry, 
and then comes separation and grading of wheat, to prevent the light grain 
making the flour dark. Then comes second grading upon two reels thus 
arranged : 



12 


12 


10 


9 



Large Wheat, 

No. I. 



Wheat, No. 4. No. 3. 

Fig. 154. 



No. 2. 



The No. 1 large wheat goes to two 4-foot ending stones. Then it goes 
to two reels clothed with No. 14 wire. 



14 


14 


14 


14 



■Ended Wheat. 



Dust from ends of Wheat. 
Fig. 155. 



Then comes air separation, the last one that is made. While the No. i 
wheat is being ended the other numbers of wheat are being elevated to sepa- 



26(5 



GRAIN CLEANING. 



rate hoppers above the ending stone. After No. i has been ended the 
stones are set closer ; then, after No. 2 has been ended, they are set still 
closer for No. 3, and so on. 

The roughing of ending stones should be in a semicircular form to assist 
the delivery of the wheat. The semolina is sent to be sized and cleaned. 
The mixed flour and middlings go to a reel covered with Nos. 11 and 10 silk. 



Middlings. 



II 


II 


10 


10 



Flour. 
Fig. 156. 



The flour is sent to the sacks as first break flour. The middlings are sent 
to the reel clothed thus : 



8 7 6 4 



More small 
semolina. 



Fig. 157. 

The first size, that which tails over, is good, white and free from specks. 
Cockle. — In harvesting wheat quite a variety of seeds are gathered with 
it — seeds which are very good of their kind, but to produce good flour these 
seeds must be separated from the wheat berry before grinding. Cockle can- 
not be separated with the " common herd," but requires a special machine 
adapted to its individual oddities. Cockle is a native of Europe — called 
Coqueltcot hy the French ; and belongs to the oxAtr Caryophillce. That variety 
causing the most trouble is the Lychnis Githago. The lobes of the calyx are 
linear and longer than the corolla, which is of a purplish red. The ovary 
is solitary, with central placenta. The virtues of cockle are few and 
slight, and its vices many. It grows even better than wheat on the same soil 
and is prolific in seed-bearing, "bringing forth plants after its kind" with 
terrible regularity and profuseness. Cockle when growing is a healthy weed 
to look at, and is very generous in branching qualities ; growing from one to 
four feet high, varying at the root from almost nothing to one inch, and 
sometimes even more in thickness. The seeds are borne in pods and are of 
a very peculiar shape, and it is on this peculiarity that machines are con- 
structed to separate it. The seed is covered with prickly spines and of a 
black color, and if allowed to get in the flour darken it to a material degree. 
Fromerly the removal of cockle was attempted by aprons of fuzzy material, 
such at felt or flannel ; the spines catching in the fuzz and being discharged, 
while the smooth wheat berries were not carried out by the apron. This, 
however, was found not to give satisfactory results, as the wheat would 
sometimes be carried over with the cockle. Rolls of hard and of soft rubber 
felt, corks and flannel rolls were then tried, with the idea of causing the 
cockle to stick in the fuzz or soft material of which the rolls were made, and 



COCKLE SEPARATOR. %<S7 

thus be removed. These rolls we remounted at such a distance apart as not 
to break the wheats, but still close enough to cause the cockle spines to 
penetrate them. This method was also found ineffectual, as the spines of the 
cockle would become worn off in the bags by rubbing against the wheat, and, 
therefore, would not stick in the rolls ; and, also, on account of the rolls 
causing loss of grain by crushing some of the larger wheat berries. The 
only method of removing cockle by mechanical means seems to have been 
arrived at by one of our Western firms.* The principle on which these 
machines depend is the difference in size and shape between the cockle and 
the wheat. Sheet-zinc cylinders are constructed having indentations on 
their inner surfaces, which are large enough to accommodate the cockle, but 
too small to hold the wheat. The whole kernels are first separated from the 
mixture of broken wheat and foreign seed, and the broken wheat and seeds 
further separated by the revolving indentated cylinders. The broken wheat 
is discharged with the whole kernels, while the cockle and other foreign seeds 
are thrown out by themselves. 

Cockle Separator. — Figs. 158 and 159 illustrate the single cylinder 
cockle machine in plan and section. The illustration Fig. 159, shows the in- 
terior of the simple cockle machine without separate attachments, the berries 
being shown very much too large. The grain falling on the sieve A, the larger 
grain is tilled over into the spout B, discharging at the large end of the cylinder. 
The small grain and the cockle pass through the holes in the sieve A, then 
through the division E, and enter the revolving indented cylinder F. The 
cockle fits ipto the indentations, and by the rotation of the cylinder is carried 
up past the first catch-board and falls into the lower cockle spout. Very small 
and broken kernels of wheat are carried liigher up past the second catch-board, 
gg, and fall into the upper spout, being thus kept free from the bulk of the 
cockle. As only the ends of the kernels of wheat fit into the indentations, as 
shown by the small cuts, Figs. 161, 162, 163, 164, they fall out before reach- 
ing the lower catch-board ; they slide back and gradually work toward the 
hopper C. Wild buckwheat is similarly taken out. Fig. 160 shows a double 
machine with parallel cylinders. A double machine is built with two cylin- 
ders on the same level, and a quadruple machine, which is a double-deck 
duplex machine. 

Fig. 165 shows Richardson's Dustless Oat Separator combined with the 
cockle separator. The oat separator removes oats, stones, white-caps, straws 
chess, dust and dry wild garlic. One section operates on the wheat as it en- 
ters the machine and another as it leaves it, this latter being for the purpose 
of removing any dirt loosened by the scouring action in the cylinder. Each 
section is independent. The machines have double eccentrics, one to shake 
the sieve riddle and the other the feed and discharge spouts. The feed hopper 
has a feed-roll to prevent clogging. The wheat enters the separator through 
a suction-spout, where it is subjected to a strong upward current of air, 
regulated by a valve, which removes the screenings, light oats, chaff, etc., the 
screenings being let through at the drop-spout cleaned, ready for market, while 
the chaff and dust are drawn into the fan and are blown out of the building ; 

* Cockle Separator Manufacturing Co., Milwaukee, Wisconsin. 

18 



268 



GRA/y CLEANIMl. 




COCKLE SEPARATOR. 



369 




270 



GEAIN CLEANING. 




COCKLE AND OA T SEPARA TOR. 



271 



the wheat then jjasses to the centre of the machine and through a series of 
sieves which take out the oats, etc., after leaving which it passes over a fine 
sieve extending the entire width of the machine, which removes all the small 



-W^' 



Fig. i6i. 



Fig. 162. 



Fig. 163. 






Fig. 164. V.\RioL's Sizes of Indentations. 



seeds, etc. The wheat then enters another suction-spout and undergoes the 
same process as when first entering the machine. Motion is given to the sieves 
by a close eccentric, which enables them to run smoothly and steadily without 




Fig. 165. — CocKi.E and Oat Separator. 



jar, thus causing the cats to pass off while the wheat is shaken through^ 
Each sieve can be cleaned, if necessary, without stopping the running of the 
machine. 



272 



GRAIN CLEANING. 



o 
5 

CL, 

Q 

z 

< 

H 

O 

< 

Oh 
< 

O 

c« 
Z 
O 

5o 
z 
w 









o 


o o 


o 


o 


o 


o o 


o 


o o 


O 


o 


O 


o 


8 




•ajnuii^- jad 




CO 


oo o 


o 


oo 


CO 


00 CO 


to 


00 CO 


o 


o 


J 


o 




suo!iriiOA3}j 




•* 


-r in 


in 


't 


■* 


T 'I- 


•<^ 


■* ■* 


in 


in 


in 


in 


m 






























^ 


-tet 


H:» 


> 

Id 


•33BJ 


C 


in 


m in 


in 


in 


in 


in in 


in 


m in 


in 


m 


■^ 


■* 


'I- 


































^ 

J 


































































3 


































c- 


•jaiauiBiQ 


C 


CO 


CO CO 


CO 


CO 


oo 


CO CO 


00 


CO CO 


oo 


oo 


oo 


00 


oo 


o 
































z 


































> 


































K 


q5 










M 


CO 




oo 
















Q 


S i 


































£ g 


c 


O 


- o 


O 


O 


r^ 


CO r^ 


in 


2 ° 


-r 


-t 


O 


in 


w 




— r 


































^ 


































O 


































S 2 










ii 


ii 




'■>> 


















































i2 V- 
.2 o 


fo 


en 


CO CI 


w 


o 


a 


en oo 


vO 


lO o 


in 


in 


o 


o 


o 




a 5 










en 


en 




m 


















fc 












































O 


•:1- 




p) 


















5j t/:" 






































































c 


O 


O en 


en 


l-H 


t> 


o o 


O 


•* -f 


00 


00 


vC 


o 


o 




















M 












M 














































■>! 


^ 




^ 


















O j5 


£ 


in 


"d- "l- 


"* 


o 


O 


in o 


r^ 


CO r^ 


o 


o 


r^ 


r^ 


o 




X S: 










in 


-1- 




in 
















bo 


__■ 


c 


O 


^ - 


en 





vO 


in O 


o 


O vD 


c 


M 


O 


o 


o 


_c 


13 
































■T3 


































3 


5 


'f- 


in 


■* CO 


^_ 


in 


^ 


vO >£) 


o 


in ^ 


•^ 


^ 


in 


in 


in 


"o tn 
































•-I 




































































j; 


c 


00 


^ -sl- 


o 


oo 


in 


vC 


vO 


cn 


c~ o 


o 


O 


'^ 


O 


oo 


-CO 






















1— ( 












O CJ 


tt 


































c 


. 


































£ 


c^ 


o o 


CO 


w 


r> 


^ 


M 




CT o 


c 

M 


OV 


in 


'J- 


■* 




































^ 


c 


o 


O en 


en 


O 


Tt- 


C 


0» 


OO 


N W 


in 


in 


in 


o 


r^ 


<u 


.c 


H^ 


M 




























M 


































a> 


^ 


in 


-r •* 


-h 


)-< 


a^ 


in o 


00 


0^ OO 


r^ 


r^ 


00 


CO 


r^ 


E 


fc. 








»-i 




























O 


in O 


O 


o 


o 


in O 


m 


o m 


o 


o 
















r^ -T 


rj 


o 


2" 


c 


in 


f) 


>~ 1^ 


T 


o 














^^ 






C4 




►- 


Ol 


M 


t-i 












•si; 


qsng ui 




o 


o o 


o 


o 


o 


o o 


2 


o o 


o 


o 


O 

o 


in 


in 


jnoH J 


3d Ajp-Ed^o 








"^ 








*"* 








■*"* 


'"' 












o 


o o 


in 


o 


o 


c 


in 


o 


o o 





in 














o 


vo en 


M 


oo 


CJ 






M 


o >o 


en 
















o 


- o 


cn 


o 


„ 


c 


o 


o 


O M 


o 


en 


^ 


M 


cn 


■auiq: 


)EIV; JO -o^r 

















o 
o 

o 


o 




















^ — 


V 


— ' 


— Y 


— 






^ 






^ 


*. 


-- 




J 




































w 






































o 




















































































rt 










































^ 










































CS 










































CU 


















- 
















c 








(D 


















U 
















_c 


c 

u 

C3 




C« 


















z 

i 












a. 








o 


















< 












r 
C 




C 


c 




c 

eel 


















tl. 
o 

Ed 
















































K 




0. 


cs 




O 










V 

b. 








J 










^ 




u 

c: 
Q. 


o 




OJ 








o 






V5 










C 
















rt 
iM 

Cw 














o 






U 




^1 








1) 












.'13 




c 




c 


3 
O 




Or- 








rt 












E , 




C 




C 


fc 




O 








o 





GRADER AND DUST LESS SEPARATOR. 



273 



In the oat separator the wheat first gets a strong upward current of air 
regulated by a valve. The screenings are let through at the drop-spout. The 
chaff and dust are drawn into the fan and blown out of the building. The 
wheat and oats pass to the centre of the machine, where one series of sieves 
take out the oats, and a fine sieve the small seeds. Capacities are minimum, 
and are subject to variation according to nature of grain and impurities and 
comparative quantity of impurities to be removed. 

The following table shows the diameters of the holes of the sizes in per- 
forated screens used for various purposes : 

When ordering, give exact sizes of perforations and size of sieve, and, if 
possible, send sample of what is wanted. 

Diameters of sizes used in grain cleaning and for other purposes : yV; tV) 



iV' "S"?' '5"4' 8) ■?""¥' 3"J> 6t) I'T) 6.4 



A- 



XI 



lii 



> "J^' ^T> 4i T^> ^' TS"' ^> TFi F> rr* 4> 8 3.na i men. 



Size commonly used for small seeds, etc., j^ inch. 

Si/.es commonly used for flax : j'g-, y'j and y'g- inch. 

Sizes commonly used for cockle : -j^, -^ and -|^. 

Sizes commonly used for taking oats from wheat : •^, W, j\-, W, -§^, W 
and \ inch. 

Sizes commonly used for cleaning barley: ■3*2-, y^-j-, fand ^x^ and y\xf oblong. 

Sizes commonly used for receiving riddles : y^g-, f and yV inch. 

Sizes commonly used for corn screens : ^, y\-,f, -|-^, f and fxf and -Jxf oval. 

In stock, yV, A, i, T6. A- tV' i. fV. f. -bt, i. f, of No. 11 zinc. 

Grader and Dustless Separator.— In Fig. 166 is shown a machine 
which is thought to combine all of the points essential to the successful 
working of a dustless receiving separator. The main points considered in 
its construction have been strength and simplicity. Other essential points of 
excellence areas follows : i. Very little room is taken up by the machine. 2. 
So little power is required to run it that it is scarcely noticeable, having no 
heavy eccentric springs, and being run at a much lower speed than most ma- 
chines of its class. 3. The separations are independent of each other, and 
are completely under the control of the operator. 4. The convenience with 
which all- the bearings of the machine can be oiled is a noticeable feature. 
5. The fan-blast can be increased to suit long spouting without interfering 
with separations or the working of the shoe. 6. The throw of the shoe can 
be shortened or lengthened as required while the machine is in motion. 7. 
The screen can be changed while the machine is in motion.* 



Size. 


Extreme 
Height. 


Height 

when 

Wheat 

enters. 


Size on 
Floor. 


Size over 
All. 


Diam- 
eter 
Pulley. 


Face 

of 
Pulley. 


Motion 

per 
Minute. 


Capacity in Bushels 
per hour. 


Wheat. 


Barley. 




I 
2 

3 
4 


5 ft. 6" 

6 ft. 

6 11.6" 

6 ft. 9" 

7 ft. 


5 ft. 3" 

5 ft. 6" 

6 ft. 3' 
6 ft. 6" 
6 ft. 9" 


32 X 32" 

34 X 34" 
36 X 36" 

35 X 35" 
40 X 40" 


4 ft- 3" 
4 ft. 6" 

4 ft- 9" 

5 ft. 3" 
5 ft. 6" 


7" 
7" 
8" 
8" 
9" 


4i" 

4*" 
5" 
5i" 
6" 


425 
425 

425 
400 
400 


25 to 40 

40 to 60 

60 to 100 

100 to 150 

1 50 to 200 


100 to 150 

200 to 250 
30010400 
45010550 



' Simpson & Gault Mlg. Co., Cincinnati, (). 



274 



GRAIN CLEANING. 



Smutter and Separator. — The Champion Smutter and Separator,* 
Fig. 167, is a vertical machine, driven with only one pulley. It is illustrated 
in section. The wheat enters the suck-spout A, where it passes through 
a current of air which removes from the wheat all straw, chaff or other light 
substances that would incline to choke and obstruct the work of the riddle. 
It then enters the riddle B, where the sticks, nails, oats, and cockle are 
removed. From the cockle-riddle it passes into the spout C, in a broad, 




Fig. 166. — "Champion" Grader and Dustless Separaior. 

thin stream. This spout is very wide, causing the wheat to enter at the full 
width of the cockle riddle quite gently, in so thin a stream that the air can 
penetrate and operate upon it in the most thorough and perfect manner. 
The shoe is operated by an eccentric at D, receiving a short endwise motion. 
The grain, leaving the lower perforated end of the spout C, falls into an 
incline trough, and is carried into the scouring-case. This consists of a 



* Made by the Simpson & Gault Mfg. Co., Cincinnati, O. 



SHUTTER AND SEPARATOR. 



275 



hollow iron cylinder, to the surface of which are attached vertical beater bars. 
The cylinder is secured to the main shaft and revolves with it. Outside of 
this beater-cylinder is the stationary perforated steel jacket, and again outside 
of the jacket in the upward flaring sheet-iron case H. 

The grain enters between the beater-cylinder and the perforated jacket, 
passes downward and out at the bottom of the case, and into the long 
discharge spout shown in the perspective view of the machine. While in the 
scouring case it is met by a strong upward current, procured by the motion of 
the fan, and fed from without through the air-tubes, E. The current passes 




Fig. 167. — Section of Champion Smutter and Separator. 

down through the interior of the beater-cylinder, and returns upward between 
the cylinder and the outer case (and both sides of the perforated jacket), 
holding the wheat suspended while undergoing the process of scouring, and 
carrying off through the fan-case all the dust produced by that operation. 
The action of the fan also produces an upward current in the large 
discharge spout which effects the second separation by carrying the lighter 
particles upward and over to the opposite side of the machine, where they 
are again met by a reverse current through the air passage F. Both spouts 
are constructed alike in this respect, and the offal falling through this 
upward current in each case is divested of chaff, dust, &c., and leaves the 
machine ready for grinding. 



276 



GRAIN CLEANING. 



Thus there are four separations effected. It is claimed by the makers : 
That the small, imperfect, or broken grains that may be driven through the 
perforations of the jacket, are saved in a clean condition, valuable, and fit 
for seed. They will fall down through the perforated cast-iron ring (which 
sustains the jacket), on to the closed bottom below the ring, be discharged 
with the wheat through the air current in suck-spout, and carried up and 
over, and be discharged through the trap-door (see cut). In many other 
machines such particles are either driven out in the fan-discharge and lost, 
or thrown down upon the floor through the open bottom. This machine 
seems to be specially liked as a barley and rye separator and cleaner. 

In setting up the "Champion" Smut Mill, pay particular attention to the 
directions, which may be found pasted upon each machine. 

Select your location ; see that the openings to all the spouts are unob- 
structed ; give the machine the proper speed with the proper feed ; regulate 
the valves till the offal is right, and the results will be sure and satisfactory. 
To do good work, a smut machine (like a man) must have good, strong 
lungs and plenty of air. 

Direction for Setting Up and Running the Champion Smut 
and Separating Machine. — ist. Level the machine by the frame, and 
see that the joint bolts are screwed up. 2d. Secure the machine firmly in 
place on the floor. 3d. Place the upper spout in position, as shown in the 
cut and indicated by the screw holes. The necessary screws will be found 
in boxing. 4th. Place the upper spout and secure as above. 5th. Put the 
shaker in its place on the top of the eccentric, and screw down the nuts on 
the springs at the sides and lower end of shaker. 6th. Brace the upper part 
of the frame against the motion of the shaker. 7th. Give the machine the 
revolutions per minute indicated in the table, and be particular to maintain 
that velocity. 8th. When automatic valves are used, to regulate the current 
of air in suck-spout, turn up the thumb-screws on the self-acting valves. 
Increasing the tension will give stronger current and heavier offal. 9th. 
Use lard oil and lard and blacklead for the eccentric. The machine can Ije 
oiled in motion. loth. Do not cut off or inclose the mouth of the long 
discharge-spout, as there must be a free inward air-current, nth. When the 
dust-spout is used to convey the dust out of the mill or to the dust-room, it 
should be at no place smaller than the fan-discharge, and when crooks are 
made they should be on a circle, and not a less circle than the circumference 
of the fan. The screens in this machine are adapted to the general demand. 



No. of 
Machine. 


Extreme 
Height. 


Height 
where 
Wheat 
enters. 


Size on 
Flour. 


Diam. 

of 
Pulley. 


Face iif 
Pulley. 


Motion 

per 
.Minute. 


Heig:ht 
fromFloor 
to centre 
of Pulley. 


Smallest 
Capacity 
per hour. 



I 
2 

3 


6 ft. 5 in. 

7 ft. 3 in. 
7 ft. 6 in. 
9 ft. 


5 ft. 7 in. 

6 ft. 4 in. 

6 ft. 6 in. 

7 ft. 6 in. 


25 X 25 in. 
28 X 28 in. 
30 X 30 in. 
33 ><33 in. 


7 in. 

8 in. 
g in. 

10 in. 


4iin. 

5 in. 

6 in 

7 in. 


700 

650 
600 
550 


9 in. 
lo\ in. 

12 in 

13 in. 


15 bus. 
30 bus. 
50 bus. 
80 bus. 



WHEAT BRUSH. 



277 



Wheat Brush. — In the Champion Wheat Brush * Fig. i68, there is a 
hand wheel and lighter burr, by means of which the machine may be made 
to brush hard or light, as desired. There is a steel perforated case from the 
brushes to work against, the same as in the Champion Smutter. 

We have had prepared the following table showing the pulley 
diameter and width, number of revolutions per minute, height of centre 
of pulley, capacity per hour in bushels of wheat and barley, weight 
ready to ship, size on floor, life of screens, brushes, etc., of the Champion 
Combined Separator and Smutter, Brush and Separator. " The wheat is fed 




Fig. i68. — Champion Wheat Brush. 

into a hopper, so arranged that it can be placed at either side of the 
machine, into which the wheat can be spouted from any direction. From 
the hopper the wheat passes into the separating trunk through a strong 
current of air, where all light stuff can be drawn off. It is then spouted 
into the machine, and falling upon the centre of the concave cylinder head 
is distributed equally around and against the perforated case. It is here met 
with a strong upward current of air, which in conjunction with the rings on 
the case will hold the grain long enough to do all the brushing required. In 
leaving the machine, the wheat passes through another strong current of air 

* Simpson & Gault Mfg. Co., Cincinnati, O. 



278 



GRAIN CLEANING. 



in the discharge spout, taking out all remaining dust, and leaving it polished, 
ready for the stones. The machine can be oiled while in motion. As the 
bearings are iron bridge trees, with babbitt-metal boxes, and isolated from 
the wood, it is absolutely free from danger of fire." 



Size. 


Extreme 
Height. 


Height 
Wheat 
enters. 


Size 

on 

Floor. 


Diameter 

of 
Pulley. 


Face 

of 

Pulley. 


Motion 

per 
Minute. 


Capacity 
Hour. 


To 
Centre 

of 
Pulley. 


I 
2 

3 


6 ft. 3 in. 
6 ft. 6 in. 
6ft. Gin. 


5 ft. 6 in. 

6 ft. 

6 ft. 6 in. 


28 X 28 in. 
30 X 30 in. 
33x33 in. 


9 
10 
10 


5 
6 
6 


500 
450 
400 


30 
50 
80 


10 in. 

10 in. 

11 in. 



CHAPTER XX. 

WHEAT DRYING AND HEATING. 

Drying Wheat— Heating Wheats— Generators for ■\^■heat Heaters in Water Mills — Thermometer 

Attachment for Wheat Heaters. 

Drying Wheat. — It is essential that flour which is to be sent abroad 
should be thoroughly dried, if it is to be kept in good condition. It is not 
quantity but quality which causes the miller the most anxiety. The miller's 
art consists in blending different kinds of wheat coming from different parts of 
the country, and possessing individual qualities, so as to produce the best 
results. Wheat ripened under the hot southern sun is more brittle and con- 
tains less water than that grown out west, and American wheat is from ten to 
twelve per cent, dryer than European wheat. If the wheat is not properly 
prepared, loss of flour is entailed. 

The bran of dry wheat, from its extreme brittleness, is apt to break up 
fine and discolor the flour ; so the miller frequently sprinkles it to soften the 
bran and reduce its brittleness. If, now, instead of doing this, he would heat 
his wheat, the moisture still remaining might, by vaporizing, be utilized to 
soften the bran, and prevent it from mixing with and discoloring the flour. 

Heating Wheats. — It often happens that the best flour is made during 
the hottest months, as the summer heat dries the moisture out of the kernel 
into the husk. The wheat heater permits the miller to get a uniform grade of 
flour the whole year round, and causes the bran to come off as nearly a whole 
shuck as possible. Hard, flinty or dried wheats especially need heating, as 
their bran is always brittle. Less power is required for grinding heated than 
unhealed grain. Hard and soft wheat mixed together are better blended 
by heating than by any other means. If wheat, after being hot, loses its heat, 
it becomes more brittle. The skin is tough only so long at it is hot. Over- 
heating by allowing the feed to be shut off without shutting off the steam in 
the heater, causes the wheat in the latter to be gummy and to start feeding 
with difficulty. It is not necessary to have a heater for each run of stone. 

In putting the wheat heater in place, cut in a plank a round hole the 
diameter of the inside of the hopper, fasten this plank to where you wish to 
bring the wheat from the stock hopper, bolt the hopper to this plank, or 
fasten it to the floor if convenient, and make your connection with the steam 
pipes as direct as possible. Be sure to use a large enough pipe. Three 
globe valves will be required, one on the boiler and one each for supply and 
exhaust. These supply and exhaust valves should be so placed that the 
miller can stand on the floor and handle them. The exhaust should be wide 
open to let the exhaust steam blow out when steam is turned on, and then it 



280 



WHEAT DRYIN-G AND HEATING. 



should be closed so as barely to let the condensed steam run out. When- 
ever the mill is stopped the steam supply of the heater should be shut 
off and the exhaust opened. This prevents the wheat standing in the heater 
from becoming superheated and gummy. To make a first-class flour to stand 
a sea voyage, the wheat must be dried. 

The heater is, in the opinion of some millers, good to use with rolls in the 
winter where the wheat is frozen. In most mills the temperature of the wheat 




Fig. 169. — Rice's Steam Generator for Wheat Heaters. 



as given by the heater, is guessed at, whereas there should be a thermometer 
to indicate exactly what the temperature is. As regards dampening the 
wheat, it is all wrong, because there is already enough moisture to toughen 
the grain in passing through the wheat heater, and as it is desirable to have 
the chops as dry as possible. Every particle of water added as water or as 



GENERATORS FOR WHEAT HEATING. 



281 



steam will cause damp grinding. Dampening by steam or by water is 
prevalent in the Western and Southern States. 

While English wheat generally contains enough moisture in itself to 
toughen the bran when heated, many others require to be dampened. 

One trouble sometimes experienced is in the use of heaters for gradual 
roller reduction. It is found that after the first break (during which the 
bran is preserved in good shape) it becomes so dry that it pulverizes even 
worse than if the heater were not used. 

No tobacco grower would be foolish enough to undertake to manufacture 
his material without first preparing it so that it may work to best advantage. 
Yet there are many millers who manufacture their raw material just in the 
state received, whereas it needs drying or heating. This simply makes the 
good conditions of June and July continue all the year round. 

There are many excellent wheat heaters in the market ; the writer is not 
prepared to say which is the best. Welch's, Gratiot's, and the Star have a 
large sale. 




Fig. 170. 



Generators for Wheat Heating. — There are many water mills 
which would put in steam wheat heaters if they had any means of generating 
the small quantity of steam to supply the heater. To meet this demand 
there is offered by C. B. Rice & Co., No. 218 E. Washington street, 
Chicago, an ingenious device requiring little attention. 

Fig. 169 shows a vertical lengthwise section of this generator. The fire 
is built on the grate G, and the gases of combustion pass up among the water 
tubes P, which connect the upper and lower spaces of the shell. The water 
is introduced from the tank through a pipe, B, and when it reaches the proper 
level, the float I rises and cuts off the supply. Equilibrium is maintained 
between the tank and the boiler by means of the pipe C. The steam passes 
through the pipe E to the heater. N is a simple form of safety valve. K is 
the fire door and M the smoke passage. The generator has the proper blow- 
off and gauge-cocks. There are two sizes made, standing 48 and 52 inches 
in height, and weighing 280 and 375 lbs. respectively. A number of these 



282 WHEAT DRYING AND HEATING. 

are in use in water mills as well as for steaming feed and other farm pur- 
poses. 

Thermometer Attach.m.ent for Wheat Heaters. — The problem 
of measuring to a fine nicety the degree to which the grain is heated has 
been very successfully solved by a thermometer* attachment, Fig. 170, 
adapted for any wheat heater. The idea is to place the thermometer in 
such a position that it shall not be affected by external temperature, but, at 
the same time, shall be capable of indicating the changes in temperature of 
the heated grain. This has been accomplished by attaching a thermometer, 
with an accurately graduated scale, to the discharge pipe of the heater. 
The thermometer tube is bent and penetrates the discharge pipe at an angle 
of about 135°. By bending the tube in this manner the bulb is brought into 
a central position in the discharge pipe, and wholly surrounded by the grain 
as it comes directly from the heater, registering therefore with great accuracy 
the temperature to which the wheat is heated. 

* Made by W. X. Durant, Milwaukee, Wis. 



-=3o8J>- <gog=- 



CHAPTER XXI. 

GRANULATION AND GRINDING. 

General Classification of Granulating and Grinding Devices — Disc Milling — Material of Discs — Burr 
Millstones — Oscillating Upper-Runner Horizontal Mill — Oscillating Under-Runner Horizontal 
Mill — Rigid Runner Horizontal Mills — Under-Runners — Vertical Mills — Iron Discs — Iron 
Cones — Methods of Driving Rolls — Cylindrical Rollers — Single Roller Working against a Curved 
Face — Materials of Rollers — Surface of Rollers — Grooved Chilled Iron Rolls — Smoothed Chilled 
Iron Rolls — Smooth Porcelain Kiscuit Rolls. 

Granulation and Grinding.* — The question of granulation or grind- 
ing is one having so many divisions and subdivisions that its treatment alone 
could be made to fill a volume of considerable size. The double title, "granu- 
lation and grinding," is used because these two operations, while not exactly 
the same, have an intimate connection, and may be effected upon the same 
machinery with but slight changes therein. We may state, as the difference 
between granulation and grinding, that grinding may be considered as reduc- 
ing to powder, and granulation reducing to grains. This difference may be 
caviled at by some, but in any case it is a distinction that we are going to 
make and adhere to for the purpose of clearness and preciseness 

The first broad distinction that may be made would be into disc, roller, 
beater and blast machines ; the most generally used being the first-named. 
The first might be called plane milling and the second convex, because in the 
first the reduction is done between plane surfaces only, and in the second it 
is done between a convex and an opposing surface. In disc milling both grind- 
ing surfaces are always in opposition. In roller milling there are two styles, 
one in which a single roller works against a concave, and in this one of the 
opposing surfaces is always in opposition and the other changes. Where 
there are two rollers working together, there is but a line of each surface in 
contact, and this changes constantly. In the beater machines, projecting 
pins, in rapidly-revolving cylindrical cages, reduce the material by a succes- 
sion of blows against the beater pins, the walls of the chambers, and against 
each other. In blast machines, of which there are only a few in use, a 
powerful blast of compressed air is used to drive the material between the 
roughened walls of the two fan-shaped plates placed closely together. 

There are employed in granulation and grinding the following devices : 
burr millstones, with either upper, under, or vertical runners, and either rigid 

* It having been urged by a practical miller, to whom vi'as intrusted the task of criticising the manu- 
script of such portions of this work as refer solely to millmg matters, that it was " as absurd to describe 
a. mill to a miller as it would be to describe a case to a compositor Jor an oven to a baker," the writer 
begs to say that in the professions of engineering, architecture, etc., the classifications and descrip- 
tions in text-books and works of reference are found to be of special value, and the more thoroughly 
posted a professional or a practical man in those professions may be, the more highly detailed classi- 
fication, descriptions and specilications are appreciated. 

19 



284 GRANULATION AND GRINDING. 

or oscillating; roughened or corrugated iron discs; roughened or corru- 
gated iron cones, working in concaves ; rollers of porcelain, stone, smooth 
and corrugated iron and steel, all singly or in pairs, with equal or with differ- 
ential motion ;* and percussion or attrition machines. Some of these exist 
in great variety ; and with each of them the miller has his choice of a num- 
ber of processes and variations thereof. We shall describe each of these in 
detail under a separate heading, and also treat the processes separately. 

A German maker is experimenting with porcelain block discs, the use 
of which appears plausible, and even glass millstones are seriously proposed. 
Since writing the above, conical rolls are advocated. 

Disc Milling. — In disc milling there are two discs with their axes in 
the same line, and their flat faces in opposition.! The axes are generally 
horizontal, although in small sizes they are vertical. The material employed 
is generally burr-stone, although there are used other kinds of stones, and also 
porcelain and glass blocks, cast iron, etc. In those mills having vertical 
axes the upper stone is usually the runner, the lower or bed being stationary, 
although there are many mills in which the under stone is the runner, the 
upper one being stationary ; and in one experiment both stones were made to 
revolve in opposite directions. 

The axis of the runner is generally adjustable lengthwise, to regulate the 
distance between the two stones, and also in a plane parallel with the disc 
face and in every direction, so that two faces may be placed and kept in 
exact parallelism. In upper-runner mills the spindle of the runner always 
passes through a suitable eye in the bed-stone. In under-runners there is no 
need of an eye in the runner. Vertical mills correspond to under-runners in 
that the spindle of the runner does not pass through the stationary stone. 

There are two ways of driving the runner. One is that by which the 
driver is rigidly attached to the runner, and exact parallelism of disc faces is 
secured and maintained by the accuracy with which the spindle is placed 
exactly in the centre of and at right angles to the disc. Such a driver is 
called a stiff driver, and the runner is called a rigid runner. In the other 
and the more prevalent type the runner is mounted upon a pivot upon the 
upper end of the spindle by means of a cross piece or bail bridging across 
the eye, and which engages with the horns of a forked driver attached to the 
end of the spindle. This is called a balanced runner or oscillating runner. 
In it the runner is permitted to accommodate itself in parallelism to the sta- 
tionary disc. In vertical disc mills we find sometimes the stationary stone 
adjustable instead of the runner. 

Material of Discs. — Having spoken of the method of mounting the 
discs we will next consider the material of which they are made. The most 
common is burr-stone, generally from La Ferte-sous- Jouarre, France.J There 

* Prof. W. D. Marks calls the author's attention, as this chapter goes to press, to the advantages of 
hyperbolic rolls, which are of a form generated by a " hyperboloid of revolution," instead of by a 
rectangle, which generates a cylinder. 

+ There are also mills in which there are three stones— the central one double-faced, and revolving 
between two stationary stones in the same line ; the axis being horizontal. A still further variety has 
two discs, set eccentrically one above the other ; the axes vertical and parallel ; either or both discs 
rotating. 

X See Chapter XXII. — Burr-stones. , 



DISC MILLING. 285 

are also Esopus, Cologne, and Peninsula stone, granite, with other stones, 
though employed very little. Discs made up of blocks of porcelain, biscuit, 
and of glass blocks have been tried, but we have no record of their per- 
formance. Cast-iron discs have long been employed for the rougher milling 
reduction, such as corn grinding, but they are now coming into use for the 
most delicate reductions of the later and more complicated milling systems. 
It will be seen that under the head of discs we have a large variety of mate- 
rial, and a still greater number of combinations of methods of mountings, as 
either the upper-runner, the under-runner, or the disc with horizontal axis, 
may have either stiff or balanced drive. 

Burr Millstones. — The burr-stones of disc shape are the oldest and 
most extensively employed means of granulating. The materials we de- 
scribe in full in Chapter XXII., the mounting and running in Chapter 
XXIII. , and the mode of dressing in Chapter XXIV. It remains to compare 
here the various classes of mills — upper and under runner, rigid and 
oscillating. 

Oscillating Upper-Runner Horizontal Mill. — This is the oldest 
and best known. It consists essentially of a fixed circular-faced level bed- 
stone, through which passes a revolving spindle, on which as a pivot is bal- 
anced a heavy runner hung at a point a little above its centre of gravity on 
an iron cross piece or bail, which engages with the horns of a driver revolving 
with the spindle. Through the large opening or eye of the upper revolv- 
ing stone the feed falls upon a fixed or dead surface, from either a hopper 
or a silent feeder. In the first case the hopper has a " shoe," which is 
generally sharply vibrated by a damsel.* 

The detailed instructions in Chapter XXIII. are for mounting upper- 
runner mills. 

In these mills the pressure, and hence the fineness of grinding, is to a 
certain extent given by the weight of the runner, usually very considerable, 
although the lighter screw is used to govern it somewhat. 

Oscillating Under-Runner Horizontal Mill. — In this the upper 
stope is fixed and the lower one rotates, the feed thus falling upon a rotating 
or " live " surface. The fineness of grinding is governed solely by the dis- 
tance of the burrs as regulated by the lighter screw, the weight of neither 
stone influencing it. 

In both the above the runner is hung on a pivot so as to be capable of 
changing its plane. It is a most difficult and delicate adjustment, requiring 
the highest mechanical skill to make and maintain. 

Rigid Runner Horizontal Mills. — Mills of this class are coming 
more generally into use, especially for middlings' grinding and for " ending" 
grain, and depend for the uniformity of granulation upon the absolute ac- 
curacy and rigidity of the stone and of the spindle. 

Under-Runners. — The under-runners can be driven much faster than 
the upper. They also permit getting the grain into the bosom with a very 
small eye, and thus grind nearer the centre than upper-runner mills can. 
They are le.ss liable to choke, and run better than upper-runners do when 

* Also written " dansil." 



286 GRANULATION AND GRINDING. 

belted to an irregular power, as a saw-mill engine, the motion of which is 
very irregular. 

Vertical Mills. — These are generally small. They depend in almost 
all cases on pressure for the fineness of grinding. They, too, are either rigid 
or oscillating. The feed is different, and often assisted by a screw. 

Iron Discs. — The grinding surfaces of iron discs are generally chilled, 
either wholly or in part, and are used both for rough grinding, as for feed, 
and for fine granulation. 

Iron Cones. — Iron cones working in a conical case are used by millers 
only for rough feed grinding, although very common for drug, bark and paint 
grinding. They engender much heat, and, because of the great frictional re- 
sistance of the grinding surfaces, take great power to drive them. 

Methods of Driving Rolls. — Rolls, as we have before said, may work 
either singly, against fixed breasts or concaves, or against moving rolls. 
Working together, they may be arranged one above the other, or side by 
side, the latter being the most usual, except in those cases where there are 
three rolls, one above another, the middle one in contact with the upper and 
lower ones. Whether arranged one above another or side by side, rolls may 
divided into three classes as regards the motion received. In some, one roll 
is driven by positive means, and the other driven by friction from the first 
one. In otliers, both rolls are positively driven, and both at the same rate of 
speed. In the third class, both rolls are positively driven, but one is driven 
faster than the other. 

There is a still further method of driving in which one roll drives the other 
by friction. Of course the two revolve in opposite directions. In others, 
they both revolve in the same direction, that is, where the reduction takes 
place, one surface runs in one direction and the other in the other. 

As regards the application of power for driving rolls, the most common 
ways are by spur gears and by belts. Friction wheels and link belts have 
been proposed, but are not yet in ordinary use. 

Cylindrical Rollers are used in pairs,* and with equal speeds have 
a nipping or crushing action. Used with differential speeds they have a cutting 
or shearing action, more nearly approaching that of millstones than the 
cracking of equally speeded roller-pairs. 

Single Roller Acting against a Curved Face. — This has the 
effect of the differently-speeded rolls, but the contact is a surface, as with 
burrs, and not a line, as in roller-pairs. 

Materials Of Rollers. — As regards the materials employed, we find 
stone, steel or chilled iron and biscuit (miscalled porcelain). Some grades of 
stone have a natural gritty or cutting substance, and these are generally 
dressed smooth, but not polished, for granulation, although in one case, 
where a single roller is used, rubbing against a concave stone breast, longitu- 
dinal recesses, like furrows, are made, to facilitate feed and reduce heating, 
and possibly otherwise influence the grinding. 

Surface of Rolls. — Chilled cast iron and steel are sometimes smooth- 
surfaced when simply for sizing middlings or flattening germs, but are gen- 

* In three high rolls the principle is that of the roller pairs, the central roll acting as a member of 
two pairs. 



ROLLS, ETC. 287 

erally grooved, either straight or spirally, generally the latter. Steel is but 
little used. 

The size, pitch, sharpness, &c., of the grooves and the difference of the 
speeds largely influences the output of the mill, and should be carefully, 
chosen with reference to the special work to be performed. 

Grooved Chilled Iron Rolls. — Grooved, fluted, corrugated, or rifled 
rolls are made of the best cast iron thoroughly chilled and then either 
grooved straight or rifled by special machinery. The grooves are in all cases 
parallel to each other, but generally run spirally with a twist around the roll, 
and in some cases have very decided and sharp edges of the same outlines 
as the teeth of a hand rip-saw, while in others they have rounded edges. 

Smooth Chilled Iron Rolls, — Chilled iron rolls with smooth sur- 
faces are used for crushing wheat, sizing or reducing middlings, and rolling 
coarse middlings and tailings in order to extract the germs of the bran specks. 
They give the best results as to quantity and quality after they have been in 
use a few months to work off their initial smoothness of finish. 

Smooth Porcelain Biscuit Rolls. — The smooth biscuit or so-called 
porcelain rolls have many advantages over chilled iron or steel, especially in 
the reduction of middlings into flour. The reason of this is that the chilled 
iron soon becomes smooth and glassy, having less grip or grinding quality 
than when new and requiring more power. The unpolished porcelain roll 
has a dull, velvety surface, with a capacity of adhesion which enables it to 
act upon the smallest particles of flour and to separate them. It is said, too, 
that chilled iron discolors the flour, making it bluish or gray.* The porcelain 
biscuit is said to be so hard that nothing but the diamond will cut it, although 
the writer has not been able to verify this statement, and doubts it. It is in- 
different to all chemical influences, and has no tendency to cake the crushed 
meal, especially with the middlings and tailings of soft winter wheat. Porce- 
lain rolls feed the easiest. There is said to be over 6,000 porcelain rolls in 
use in this country and in Europe. 



^4=^ 



CHAPTER XXll. 

THE BURR-STONE. 

Various Stones used for Grinding — Burr-stone Proper— La-Fert^-sous-Jouarre — Ordinary Millstones. 

Materials of Millstones. — There are employed for milling pur- 
poses, sandstone, granite, basalt, lava, porphyry, and burr-stone proper. 

The quartz sandstone of Perg, in Upper Austria, is much used for rye 
milling. It works better on dry than on moistened grain. Can be used for 
either breaking or flouring. 

The millstone of Tilleda, in the Kyffhauser, is a sharp, open, red sand- 
stone, suitable for either breaking or flouring. 

The Miinden stone is a white, sharp, fine porous sandstone, used in north 
Germany on rye. By reason of its grindstone-like action, it is generally used 
working against Crawinkler stone. 

The Jonsdorfer stone is like the Miinden. It is found near Zittan, and 
used in Bohemia in large runs for hulling and in small ones for rye grinding. 

Rhine stone (lava or basalt,) comes from Andernach, is of a dark, grayish 
blue color, very porous, and was once much demanded for wheat milling. 
This stone is not too hard, and dresses easily and sharply. Somewhat like 
it is the stone from A^olvic, in Auverge. 

The Crawinkler and Ohrdruffer quartz porphyries, come in very hard 
but porous masses. The harder are used for wheat, and the softer on rye. 
The color is gray, sprinkled with felspar crystals. 

The Perg quartz granite is very hard and durable, but has not the sharp- 
ness of pores peculiar to the French burr-stone. 

The trachyte quarries of Hungary have been worked for 800 years. The 
ancient Sarosptaker quarries yield good burr for low middlings. Sardinia 
and Germany also have quarries. There is a quarry of valuable material 
in Randolph County, W. Va., near the great Cheat Mountain limestone belt, 
sixty miles south of Grafton. This stone is pronounced good for flour and 
corn, and unusually hard. There is also burr-stone in Georgia. 

Esopus stones, from Ulster County, N. Y., are good for corn or oats, 
making soft pleasant meal for family use. They do not keep their edge 
long. Stones are sometimes made with a sandstone heart and a burr skirf, 
and cracked about eight inches from the skirt inward. Such stones will cut 
up the bran. Granite would make a better heart than sandstone. 

Burr-stone Proper. — Burr-stone occurs in the uppermost stratum of 
the globe. Its texture is cellular, the cells being irregular in number, shape 
and size, and often closed by fine flakes, or by cross fibres of silex. Its 
fracture is straight. It is about as hard as flint, but not so brittle, and it 



MILLSTONES. -^ 289 

varies from the most open to the closest texture possible. It is sometimes 
filled with shells or with impressions of vegetable matter. 

The stones are cut out by a series of iron and wooden wedges, gradually 
and equally inserted. For commercial purposes they are made into solid 
stones, blocks, quarters, panels and half panels. The blocks weigh from 
75 to ICO pounds in the rough, the large size measuring in the rough 12 x 20 
inches, the small size 14 x 8 inches. They should be dried and seasoned for 
one or two years. Every block should be tested with a pick for temper and 
texture. It takes long experience to judge correctly the different qualities 
of burr. 

Some blocks come as small as four inches square, and some as large as 
twenty-four inches on a side. The Epernon stone (more commonly known 
as new stock) is found as large as six feet in diameter. While the usual rules 
for judging the quality of a burr-stone by the color will be found useful, they 
are by no means invariable. 

The quality of the burr-stones varies with the depth from which they are 
taken. The clear white or variegated stone, resembling marble, is often 
thought among the best for all uses, being free and hard, and holding an edge 
well. For corn, the stone with a pale bluish cast is chosen, being of a keener 
temper and not so subject to soft open places.* It resists the pick more than 
any other, but once dressed proves the best for hard grain. This burr is 
not recommended for wheat, as if allowed to get smooth it is apt to heat and to 
grind wheat oily. If dressed at all rough it will make specky flour and grind 
harsh. The cream, light gray and drab stones are among the best. Dark 
or lead-colored stock is vitreous, glazing soon and heating the chop. In 
the genuine anchor " R" blocks there are about twelve different kinds as re- 
gards color, texture and openings. Anchor " R " blocks are sharp, close and 
hard. In anchor "R" edge blocks the grain runs from face to back. They 
are of different colors, white, yellow and gray. " W " blocks are medium open, 
yellow and gray color, medium hard, fine grain. " S " blocks are large, a little 
more sandy than anchor " R " and " W," and have a white, yellow and violet 
color. " B " are of inferior quality, coarse grain and dark. "A" blocks re- 
semble anchor " R," being, however, a little more gray in color. 

New stock blocks are flinty, very sharp, and will almost cut glass. Edge 
blocks are the best grinders for wheat. In these the grain runs straight 
through. They do not require to be cracked often as they keep sharp naturally. 

The old stock is considered the best for wheat, being more porous than 
the new ; but there is very little of it left, and old stock burrs are in conse- 
quence much dearer than the new. 

For wheat and middlings close texture old stock is preferred. New 
quarry or new stock is generally preferred for corn. 

Rye takes a softer stone than wheat does. 

A good millstone is told by its even grit, even texture, even openings, 
even color, and above all by its close resemblance to one solid piece of stone 
with the joints hardly distinguishable. The blocks should be joined the 
entire depth and not simply with a face joint. 

* Kick considers the bluishwbiite burr the best, ne.\t the yellow, then the reddish, and last the white. 



290 



THE BURR-STONE. 



Good workmanship will insure close joints from the face to the back 
'Ihe burrs made by the Simpson & Gault Manufacturing Company are 
claimed to carry out this principle. Figs. 171 and 172 show the right and 
wrong way of making joints. 

Where one selects his own burrs, it is best to choose a block of the de- 
sired quality, and to demand that the rest shall be the same in every par- 
ticular. A stone of part soft and part hard blocks will not grind well and 
cannot be kept in good face. 

If possible, have all the blocks run from eye to skirt, and in any case have 
all the joints made close. No matter what material is chosen, the stone 
should be built up of blocks of equal hardness and porosity throughout, 
and as far as possible of the same size on similar parts of the stone. In the 
runner the blocks should be of the same height or thickness. French-built 




Fig. 171. — Right Way. 




Fig. 172.— Wrong Way. 



burrs are apt to be deficient in workmanship and in selection of stock. 
"Cask" millstones are built of blocks, fitted and numbered at the quarry 
with a view simply not to waste stock, and without any consideration for the 
quality of the stone. 

Burr-stone cement is used in the joints, plaster- of-paris in the back. The 
cement is partly composed of pulverized burr stone. This cement will stand 
wheat and middlings grinding nearly if not quite as well as the stone, and it 
is hard to distinguish the cement from the stone. Plaster should never be 
used to cement the blocks together. White lead and glycerine, for filling 
holes in stone faces, cause poisoning. 

La-Ferte-SOUS-Jouarre. — La-Ferte-sous-Jouarre, the centre of the 
millstone industry, is in the middle of the valley formed by the Marne, 
and running east and west. On both sides of this river are hills from 60 to 70 
meters above the water level. The geological characteristics of La-Ferte 



LA-FERTE-SOUS-JOUARRE. 291 

show all throughout the upper class of tertiary rocks, i. The bottom of the 
valley is coarse limestone with argillaceous and limestone masses surmounted 
by grit rock and retiring on green sand. 2. The second part incloses, in 
certain places, separated beds of gypsum covered with marls. They rest on 
a siliceous limestone. 3. Beds of siliceous and micaceous sand under siliceous 
grit and over argillaceous marls. 4. Small beds of marine formations, well 
characterized, on the southern hill, by numerous fossils. 5. Siliceous burr- 
stone, compact and porous, enveloped in clayey bands and siliceous and mica- 
ceous sands. The value of the burrstone is very variable in different quar- 
ries. 

On the northern hill, at La Justice, there are quarries presenting all the 
elements of a complete study. At this point the burrstone deposits have a 
stratified form, below beds of clay having a thickness of from three to five 
metres. The millstone beds also vary in thickness, but generally between 
three and five metres. The deposits worked for burrstone rest on a clayey 
bed containing nodules of millstone, used for building purposes. The stra- 
tum of five metres of millstone is far from being homogeneous, and entirely 
good for making burrs. The upper bed is a white millstone, used for build- 
ing. That immediately below contains the best stones, used for runners. 

At the south the millstone rocks do not present, as at the north, any strat- 
ification ; they are conglomerates more or less voluminous, dispersed here 
and there among clays and siliceous and micaceous sands varying from red- 
dish brown to yellow and white. 

The stone fit for mills is variously colored, from white to quite deep 
brown, including clear gray, bluish gray, sky blue, rose violet, barley-sugar 
yellow, grayish yellow and brownish yellow. These colors are produced by 
mineral oxides, and have no connection with the quality of the stones. To 
get at the stones the earth is removed above them by inclined railways. 
When uncovered, if the upper part is not good enough for burrs, it is blasted 
away until good stone is found, and this is carefully removed, according to 
the lines of stratification, and not broken up. When there are no such 
cracks, longitudinal grooves are made, and the stone is wedged out in blocks 
following the natural fissures. In some quarries water is abundant, and is 
removed by steam pumps, or by siphons when the lay of the land permits the 
latter. 

After coming from th« quarry the stones are sorted according to their 
respective qualities, and then by "lots." A "lot" contains enough material 
to make a millstone of medium diameter, of even color, grain and hardness, 
and of perfect homogeneity. I need not dwell long upon the absolute neces- 
sity of having the two stones which compose the pair or run of burrs made 
up of blocks evenly matched as regards hardness, porosity, etc., so that each 
stone may be as nearly as possible like one solid block. 

In some establishments the stones are cut and dressed by hand. In that 
of Roger, Fils & Co. machinery is employed. The manufacture com- 
prises several distinct operations, i. Blocking out the sections, cutting them 
and perfecting the joints. 2. Assembling and cementing the blocks. 
3. Hooping. 4. Truing up. One machine trues the face of each piece 



.) 



292 



THE BURR-STONE. 



which enters into the structure of a burr, and trues also the joint faces. A 
reciprocating table bears one or more pieces of stone which are faced up by 
a rapidly revolving tool bearing diamonds set "staggering." The tool has 
an automatic cross feed, so that each diamond levels the ridge left by the 
preceding one. The centre of the millstone being finished, its face is planed 
and its sides are cut to a right angle with this plane. A special machine is 
employed in assembling. This machine has a circular cast-iron bed-plate 
fixed and centered accurately on the eye of the burr, and also a movable 
straight-edge or arm also of cast iron and turning around a spindle passing 
through the centre of the bed-plate. This arm has a sliding scale permitting 
of determining exactly the diameter and the circumference of the burr. It 
has a strong rib, giving great rigidity and permitting of making stones per- 
fectly plane and round no matter what the unevenness produced by the com- 
position which fills the joints, each piece coming successively to bear upon 




Fig. 173. — Burr-stone Qc^vrry. 

the arm, which resists all efforts tending to twist the surface of the burr. In- 
stead of plaster as a bond for the blocks composing the burr, there is now 
employed by some niakers a peculiar and very hard and durable lime 
cement. The iron hoop is then heated and shrunk on the rim about five 
centimetres (two inches) from the working faces, binding the sections very 
strongly together. 

As the runner is to turn upon a vertical spindle, it must be of uniform 
weight in all parts. The back must be carefully filled up to a uniform sur- 
face. The stone rests on an iron tripod, on which is fixed an arbor passing 
through the centre of the eye. An iron bar carrying a horizontal cutting 
edge and another cutting vertically slides against the bearing, which embraces 
the central arbor so as to answer for any diameter of stone. The bearing 
touches a distance collar, sliding in the spindle and fastened by a set screw, 
thus regulating the thickness of the burr. Revolving the apparatus the run- 



\ 



BURR-STONE QUARRY, ETC. 



293 



ning face of the stone is rendered truly plane. Iron polishing blocks, with 
suitable handles, give it a marble-like surface. 

Plaster being essentially hygroscopic, and hence affected by atmospheric 
influences, stones should not be jointed with that material. During the opera- 




FiG. 174. — Burr-stone Quarry. 



tion of truing there are placed on the running side of the stone cast-iron bal- 
ance bo.xes containing adjustable weights. 

The next and most important operation is dressing. This is the uniform 
and regular surfacing of the working surface of the burrs, and has generally 
been done by hand, in all countries, with a very sharp-edged hammer — the 
"bill" or "pick." The workman was compelled to breathe the siliceous 
powder produced by the blows of this pick. This occasioned serious mal- 
adies, rendering the substitution of machine work of double advantage. The 




Fig. 175.— Millstone Making. 



French Society of Encouragement of National Industry offered a prize of 
4,000 francs for the solution of this problem, and awarded it to Mr. Roger, 
Jr. His machine consists of a large face-lathe, having a tool-holder moving 
radially and carrying a spindle around with from eight to sixteen diamonds 



/ 



294 THE BURR-STONE. 

placed staggering. The lathe in rotating presents each part of its face suc- 
cessively to the action of the diamonds, so that each cutting forces another 
out of the ridge left by the last. It is necessary to give the runner a certain 
amount of bosom, commencing at the eye and running to nothing at about 
fifteen to twenty centimetres from the circumference. The action of the 
diamonds avoids the bruises caused by the shock of the pick, and at the 
same time produces a more regular and durable dress. The result is less 
waste of stone and of time, less heating, greater yield and white fiour. 

Fig. 173 represents the interior of a millstone quarry, and Fig. 174 the ex- 
cavation opening into the quarry. Fig. 175 represents the interior of the 
millstone factory. 

Ordering Millstones. — State size, which way they are to run, whether 
with or without furrows, and, if furrowed, the speed they are to run, the 
quality of grain to be floured, preference (if any) as regards openness, pre- 
ferred thickness of the bed and of the runner, what kind of irons pre- 
ferred. If no irons wanted, give size of eye desired. 



-^ 0.+^ 



CHAPTER XXIII. 

MOUNTING THE BURRS. 

The Millstone —Building Up the Burrs — Size and Weight of Stones — Hurst Frames — Hoppers and 
Hopper Frames — Pinion Jack — Size of Pulleys — The Spindle — Different Forms of Cock- 
heads — Setting the Bed — Tramming and Bridging — Iron Jackstick with Level — To Make 
a Tram — Bush — Tram- Pot — Stiff vs. Oscillating Drive — The Balanced Bail — Ordering a Bail 
— Drivers — The Dane Driver — Equilibrium — Balancing the Runner — Standing Balance — 
Running Balance — Centrifugal Force — Radius of Gyration — Putting in Running Balance — 
Point of Suspension — The Damsel Feeders — Automatic Stone Lift — Iron Burr Crane - Oiling 
Mill Spindles — Fitting a Nevkf Back — Cost of Building Up. 

The Millstone.— Nine out of ten of the burr-stones that have been 
working during the last twenty years have been badly hung, ignorantly 
dressed and wrongly run ; nevertheless, they have done nearly all of the 
flouring of the world. If, then, a device so improperly cared for and handled 
is capable of doing so much and so good work as the stone has done, much 
better can be done in the future when people understand it and develop its 
capacity. 

In general it may be said, that if the stocks be well chosen, and the 
stones built up, dressed, set, hung and driven properly, excellent flour may 
be done by a competent miller. If, however, the proper precautions and skill 
are not used at first and continued, burrs need not be expected to turn out 
good work. In this matter, rolls have an advantage over burrs ; they re- 
quire less knowledge and watchful care on the part of the miller, who be- 
comes more of a mere manufacturer. 

Building Up the Burrs. — The method of accomplishing this is given 
in detail in a former chapter. We merely add a few paragraphs, suggested 
as this chapter goes to press. 

In regard to the question whether eye-blocks should be more or less porous 
or more or less close than those at the skirt, the head miller of one of the 
largest mills at St. Louis says that, for wheat-grinding, it is better that the 
eye-block should be more solid and a little harder than those at the skirt, be- 
cause the amount of surface is small in comparison with the whole, and the 
wheat passing over that surface in a whole or slightly broken condition, has 
great scouring or washing power, enough at least to keep such blocks on an 
equal plane or level with the skirt-blocks. Now, if the position of the blocks 
is reversed, the wheat acts upon the soft and most porous blocks when in 
the condition capable of doing the most scouring or washing. The conse- 
quence is that cuts or rings are formed of such numbers and depth as to make 
good granulation impossible. 

Stones have got into such a condition from the eye-blocks being soft and 
porous as to render them unfit to use on wheat, but having been faced down 
until the rings or cuts were taken out, and then put to grinding middlings, 



-V 



296 MOUNTING THE BURRS. 

have done very good work, because the middlings, acting upon the porous 
eye-blocks, allowed them to remain on an equal plane or level with the skirt 
of the blocks. The middlings not having that scouring or washing power of 
wheat, no rings were formed. 

Size and "Weight of Stones. — The five and six feet stones weigh 
from three to four thousand pounds each, bearing very heavily on the spindle 
step. Four-foot stones, weighing eighteen hundred to two thousand pounds, 
making 175 revolutions per minute, are about right for light water-power. 

Hurst Frames. — These are preferably of iron, as being more solid 
than wood ; but it is best to have a wood top which obviates the expansion 
and contraction due to changes in temperature to which the iron hurst frame 
is liable. To obviate this, especially where there is a Ime of burrs on iron 
frames, they should have wooden tops. 

It is perhaps best that the lower part of the hursts be in the basement 
on an independent foundation. Three runs of stone are very commonly 
combined in one hurst, as one under-runner for corn and two upper runners 
for wheat. 

Hoppers and Hopper Frames. — These are best made of extra 
quality pine or maple. It is desirable to have the shoe attached to the upper 
frame, which does away with the stand and permits the shoe to be removed 
with the frame, thus preventing the shoe from dropping down into the eye of 
the stone when loosened from the rolls. 

Pinion Jack. — To lift a stone pinion out of gear a pinion jack is often 
employed ; but a simpler way is with a shaft worked by handles with rigid 
stock and having short chains with hooks which are caught under the arms 
of the pinion and raised out by the turning of the shaft. 

Size of Pulleys. — It may be necessary, in order to get just a certain 
number of revolutions out of one runner, to put in a special size that might 
really be too small or too large a pulley (generally the former) on the spindle. 
But where the transmission is such as to give a choice, the following table is 
based on usual practice : 

Stone, feet diameter 2 3 3>^ 4 4^ 

Belt, inches diameter, .... 4 8 10 12 14 

Pulley, inches diameter, . . . .16 24 28 30 32 

Curbs. — The curbs should be strong, neat and tight, and, properly, should 
be built with a view to the addition of a millstone exhaust, the question of 
which is treated at length in another portion of this work. Under the head 
of " Millwrighting " will be found the detailed instructions for laying out and 
making curbs. 

The Spindle. — The spindle should be tested in the lathe before it 
leaves the shop. See that the hole in the balance rynd or the cup in which 
the cockhead works is made exactly in the centre. The driver should 
be an exact fit of the section of the neck of the spindle, allowing one-fourth 
inch from its lower face to the spindle neck for sinking in wear. As steam- 
power is often unsteady, steam mills require stronger spindles than those 
mills using water-power. The spindle should be from eight to eleven feet in 
length, the latter length being recommended as most convenient for gearing. 



THE SPINDLE. 



297 



The neck should be from ten to twelve inches long ; from the top of the neck 
to the point of the cockhead nine inches. In testing the spindle the point 
of the neck and step must correspond with each other. 

The spindle should be of wrought iron, the cockhead and toe of steel. 
It is claimed by some that the bridge-tree should be somewhat elastic. 
Where rigidity is desired the spindle step should rest on the main bed-plate, 
instead of the bridge-tree being attached to the columns at a point above the 
bed-plate ; this precludes the possibility of trembling. Spindles should have 
raised collars. It would be well to have an adjustable spindle which could 





Fig. 176.— Wrong. 



Fig. 177.— Right. 





Fig. 178.— Wrong. Fig. 179.— Wrong. 

Forms of Cockhead. 



be shortened in the eye so that the bail need not be detached when the face 
of the stone wears down. 

Different forms of cockheads are shown in Figs. 176 to 179 inclusive. 
The second one, Fig. 177, is of the proper form to give free oscillation in 
every direction, as well as easy rotation. The others are bad forms in every 
way. 

Followers should in any and all positions of the spindle have a full and 
uniform pressure throughout their entire length and breadth and against the 
spindle neck. 

The ordinary form of wrought-iron spindle is shown in Fig. 180, the 
steel cockhead and toe being shown by the dotted lines to project into the 
spindle. 



298 MOUNTING THE BURRS. 

The mill spindle should be kept well oiled, because not only does the in- 
creased friction necessitate a greater amount of power to drive the stones, 
but the spindle itself becomes abraded, and may heat so as to stick in the 
step. The plan of putting a string around the spindle has the disadvantage 
that there is danger of having to take up the mill to put in a supply of tallow 
or oil. A better way is to guide oil through a small pipe, from the outside 
of the curb down below the husk frame and bottom stone, thence with an 
elbow toward the bush, just below the bush, thence through a hole or open- 
ing in the bush upward to nearly a level with the top of the bush, where a 
groove is cut just deep enough to admit the discharge end of the little pipe 
to sink below or even with the level of the top of the bush, and not be in the 
way of anything which might be used as a bush cover to keep out dirt and 
trash. By this means the spindle need not be looked after for a long time. 
Spindle bearings should be oiled each day. Tallow is the best lubricant for 
the collar ; suet answers well. Many millers prefer wood for the box 



Fig. i8o. 

around the collar of the spindle. Some prefer to fasten weights by means of 
hooks to the wedges which tighten the braces. With these the pressure is 
radially adjusted if the spindle heats or if it becomes loose. 

Setting the Bed. — Lay the stone down in its proper place, with the 
back even and solid on the timbers. Level the face correctly with wooden 
wedges between the stone and the timbers, and then, without deranging the 
level, drive wedges all around the verge, to keep it from moving sidewise. 
Clean the plaster out of the eye, wet the remaining plaster, dropping in the 
bush with the upper part half an inch above the face of the stone. See that 
the bush is exactly centred, wedge it in place, plaster up all crevices below 
with clay, then run in thin plaster on the bush next the stone. 

When the plaster is hard, put a board in the centre of the bush, find its 
centre, and make a small hole through it and pass a plumb-line. With the 
plumb-line as a guide, move the step on the bridge-tree, so that the hole in 
it agrees with the centre of the bush, then fasten the step. Now put the 
spindle in place and tighten the neck. 

Whenever the runner is taken out, the bed-stone should be tested and 
leveled if- wrong. A better plan then wedging is to have cast-iron plates in- 
serted in the backs of the bed-stones, to receive the pressure of leveling 
screws inserted in the under side of the hurst. 

Tramming and Bridging.— Take a piece of wood twenty-four to 
thirty inches long, tapering from four inches to one, cut a square mortise 
through the wide end to fit the square cockhead. In the smaller end make a 
small hole about two inches from the verge of the stone ; fasten in this a 
quill set to touch lightly and to play around the face. Fasten, the tram on 
the square neck and move the spindle gently around, noting what parts of 
the stone the quill touches. Alter the wedges or screws until the quill 



IRON JACKSTICK—B USH. 299 

touches the face equally all around. If stones are out of tram, the pressure 
will be harder on one side than on the other, causing the driving points to 
wear more on one side than on the other, while at the same time one side 
of the stone grinds closer than the other. 

The stones should be trammed every time they are dressed. When not 
in tram they will rub in parts and make dark and specked flour. An im- 
provement over the ordinary wooden board tram is the iron jackstick with 
a level, and all parts adjustable. 

The Iron Jackstick with Level is shown in Fig. i8i. It is fixed 
firmly on the spindle with the screws A E C D just below the cockhead. 
The level is adjusted by a set-screw, F. When the bubble E in the level 
retains the same position in the tube, no matter in which way the jackstick 
is turned, the spindle must be perfectly vertical. A quill, G, being fixed on 




o 

Fig. i8i. — Iron Jackstick with Level. 

the outer edge of the jackstick and brought down just to touch the floor of 
the stone, will enable one to see whether or not the bed-stone is perfectly 
horizontal. 

During this operation the bubble should be watched to see that it does 
not leave the centre of the level, which would prove that the jackstick had 
got loose on the spindle, and consequently the indications of the quill would 
not be correct. 

Bush. — A good bush not only keeps the spindle in place laterally, but 
by keeping it cool prevents it from rising and falling, and thus makes the 
grinding uniform and better. The advantages of a perfect bush are that the 
followers will adjust themselves to the spindle under all conditions, whether 
in perfect tram or "out " in any direction. When a spindle is out of tram it 
is so in one of three ways : Either it is slightly displaced laterally while re- 
maining in true vertical position, or it is reasonably central but out of plumb 
or verticality ; or both. The first case very seldom happens, the second is the 
most frequent. Now, it is evident that in such a case the sides of the spindle 
are inclined, and that the followers, in order to fit them exactly, must also be 
inclined in the same degree and direction. The ordinary bush has an ar- 
rangement for follower adjustment laterally, so that they may all be just as 
far from the true centre line of the step as the top of the spindle is. The 
more inclined the spindle is, the more inclined the sides of the followers 
must be. We must then have followers that will accommodate themselves to 
any degree of inclination of the spindle, as well as to any degree of eccentric- 
ity of the cockhead. Now, when we come to think of it, the spindle may be 
out of plumb, with regard to the central line which it ought to assume, in 
two directions — say, in a north and south direction, and in an east and 

20 



300 



MOUNTING THE BURRS. 



west direction. The follower must, therefore, have adjustability in all direc- 
tions in the horizontal plane. In order to fit the sides of the spindle, the 
centres of adjustability of each follower must be in its centres of height and 
of length. 

The Kuehne & Bryant bush,* Figs. 182 and 183, has followers with ad- 




FiG. 182. — Kuehne & Bryant Bush. 



justability in both directions horizontally, and each follower has locking 
wedges operated by screws, the gibs having double-inclined backs with in- 
clined faces connected to the gibs by vertical bearings and seats, and ex- 
tending the entire length of the followers or gibs. The followers are of cop- 




FiG. 183. — Kuehne & Bryant Bush. 

per, brass or babbitt, as desired. It will be seen that the followers have 
automatic adjustability for inclination of the spindle and for its lack of cen- 
trality. In addition to this, wear of the followers may be taken up by the 
wedge B and screw. In the cuts, C represents the iron backing of the fol- 
lower and D its brass, babbitt or copper face. 

Fig. 184 shows the ordinary bush, which is provided with a collar placed 
above it. 

* Kuehne & Bryant, Chicago, 111. 



TRAM-POT. 



301 



Tram-Pot. — Tram-pots are either centre-lift or top-lift, the latter being 
the most used. The centre-lift requires the bridge-tree to be pierced for the 
lift-rod to pass through. The top-lift is much more convenient. The tram- 
pot is often set on an arch over the line shaft. Fig. 185 shows an arch tram- 
pot to bridge over the horizontal shaft of bevel-geared mills, Fig. 186 being 
a centre-lift pot. Figs. 187 and 188 show forms of top-lift tram-pots. 

Laying off and Cutting tlie Holes for tlie Balance Rynd. 
— Lay the runner perfectly level, face upward. Fit a planed board in the 




Fig. 184. — Ordinary Bush. 

eye, divide it into quarters and find the centre, making the mortises nearly 
an inch longer and wider than the thickness of the rynd. 

The mortises for the driver must be laid off on the opposite quarter- 
marks ; there should be cast-iron boxes for the driver to work in, one-fourth 
of an inch wider than the journal. 

To make the mortises good chisels and heavy picks are needed. The 
sides of the mortises must be straight and square from the face of the 




Fig. 185. — Top-Lift Arch Tram-1'ot. 



Stone. When the box mortises are nearly the proper depth, drop the 
boxes into place to test them. Drop the driver on the spindle, fastening 
it so as not to drop off. The balance rynd being in its proper mortises and 
at the right depth, put the spindle point into the centre of the rynd and the 
sides of the driver into the boxes. If the driver rides on the bottom of the 
boxes, take them out and deepen the mortises, as the spindle point should 
have free play in the holes of the rynd, leaving plenty of room between the 
bottom of the boxes and the driver. 



302 



MOUNTING THE BURRS. 



Fastening the E,ynd and the Driver Boxes. — See that the 
rynd is true and the whole well centred ; take a smooth strip of wood the 




Centre-Lift Tram- Pot. 



width of the lugs of the rynd and the thickness of the iron ; fit this closely 
across the space between the lugs and even with that face which would be 




Fig. 187. — Top-Lift Tram-Pot. 



next the stone ; lay the small straight-edge on the lugs, and over the strip 
apply the iron square to the straight-edge. Put one edge on the centre point 




Fig. 188.— Top-Lift Tram-Pot. 



in the rynd and mark the strip ; reverse the square and mark ; if both points 
agree, that is the centre ; if not, divide it evenly. 

Place the balance rynd in the stone with the centre of the thickness of 



STIFF vs. OSCILLATING DRIVE. 



303 



the lugs even with the quarter-marks. Lay a straight-edge on the stone, and 
from the opposite quarter-marks make a line across the mark on the strip. 
This will be the centre of the stone. Lay the straight-edge on the other 
quarter-marks, and move the rynd until the centre or line on the strip is even 
with the straight-edge. If it then agrees with the other quarter-marks, the 
rynd will be properly centred. If the line is not perpendicular, the spindle 
will wear the hole to one side. 

Drive small iron wedges around the edges and sides of the rynd. Stop 
the sides of the mortises with stiff clay and run in lead until it reaches above 
the surface of the mortises, then settle it down closely with the cold chisel 
and hammer. 

To set the driver boxes put the driver on the spindle, place the boxes on 
the driver with a piece of wood a quarter of an inch thick, and a piece on 
the ends to prevent the driver touching either the ends or the bottom of the 
boxes, then drive wedges between the sides of the driver and the boxes, and 
fasten the driver in them. If the bail is not fixed perfec*-^ central in the 




stone, one side of the stone will be heavier than the other, and while standing 
the heavy side will hang the lowest. The inside of the bail should be of the 
same diameter as the eye of the stone. (See Fig. 189.) 

The eye of a 4-|-foot stone may be \o\ inches at the base,' tapering 
to 7 or 8 inches at the back, the runner stone being 20 inches thick at the 
eye and 15 at the skirt. 

Stiff vs. Oscillating Drive. — As regards the question of stiff or 
oscillating connection, it is very easy for any miller who has two runs of burrs 
to try the two side by side and judge which one is best adapted to his work. 
It may, however, be said in general terms that the stiff drive requires better 
workmanship and care than the balanced, but that modern methods permit 
much greater stiffness of the building and of the hurst, and greater accuracy of 
face, than was common fifty years ago ; hence stiff drive is now more possible 
than formerly, and gives more and more satisfaction each year, especially for 
ending, hulling and pearling, and for middlings flouring with burr-stones ; 
and the high-speed iron disc stiff-driven under-runner break machines of 
the Jonathan Mills' system owe their success very largely to the advanced 
ideas of mechanical instruction embodied therein, such as extra long bear- 
ings, ample wearing surfaces, and great rigidity of the iron frame. The 
balanced drive gives the miller a better chance to let the condition of his 
burrs deteriorate than the stiff drive does. With stiff spindles there is some- 



304 MOUNTING THE BURRS. 

times trouble keeping the driver in the runner. Where the husk frame is old 
and rotten, there will be apt to be trouble with a rigid driver. 

The Balanced Bail. — The advantages claimed for the balanced bail 
over the fixed are : i. The runner, while so supported that it shall revolve 
evenly upon the spindle, with its face perfectly horizontal, always retains this 
position while in revolution, even though the spindle does not stand truly ver- 
tical, so that if the face of the bed-stone lie perfectly horizontal, an equable 
distance may be maintained between the two stones. 2. That on raising the 
stones the bail may be freed without trouble from the spindle, while the driver 
remains attached to it. Moreover, it is not necessary, as with a fixed bail, to 
free it by force from the millstone, which is liable to cause derangement of 
the bail. The runner, while freely moving, easily yields to large or small 
foreign bodies which may chance to get between the grinding surfaces, with- 
out displacing the bail, which sometimes happens with fixed bails. 

There are, however, cases where the balanced bail cannot at all compete 
with the fixed, among which we may reckon : 1. Where the runner is very 
large and at the same time of very unequally distributed weight, making the 
restoration of the running balance very difficult. 2. When it is necessary 
that the distance between the stones should be strictly maintained, as in the 
case of pearling stones. 3. Where the distance between the two grinding sur- 
faces must be very great, so that the runner has plenty of play for oscillation, 
which would spoil the grist, or the grinding surfaces would be apt to be 
spoiled by the considerable sagging and impact of the stones. 

In ordering a bail, the maker should guarantee and the buyer should see 
that the following conditions are observed : i. The point of suspension 
of the bail must be so constructed that while strictly horizontal the stone 
may be easily depressed in any direction without showing any greater resist- 
ance in one direction than in another, otherwise the balance bail will have 
the disadvantages of the fixed bail. The driver must be so constructed as 
not to interfere with this easy motion in any direction. 2. The pomt of sus- 
pension of the bail upon the spindle must lie in the centre or axis of the 
spindle and the stone, and both axes must fall into one and the same vertical. 
3. The point of suspension of the bail upon the spindle must lie in a vertical 
line over the centre of gravity of the stone. When the centre of gravity lies 
beyond the axis of revolution, the runner is only in standing balance, and on 
the slightest resistance causing the oscillation of the runner, the latter must 
sag down in one direction and remain in this position. When, however, the 
centre of gravity of the stone and axis of revolution coincide, the runner 
will be in equilibrium, whatever its position; and if such a case were to occur 
that the centre of revolution lay beyond the centre of gravity, the runner, if 
thrown out of the horizontal grinding plane would, by its vibrations, show its 
effort to regain its original position. 4. The driving-point of the driver 
must, if possible, fall into the same horizontal plane as that in which the 
point of suspension of the bail lies, so that the pressure exerted in the trans- 
mission of the motion shall not necessitate the employment of an arm, which 
would have a tendency to throw the runner out of the horizontal position. In 
any case, the driving-point of the driver should not lie lower than the centre 



DRIVERS. 305 

plane of gravity of the stone, because the motion would then become rock- 
ing and unsteady. 5. The points of attachment of the bail in the stone 
must, if possible, fall into the same horizontal plane in which lie the working 
points of the driver. This is especially desirable where the driver grasps 
the bail, as in most arrangements, for if these conditions are not sufficiently 
fulfilled, the pressure of the driver on the bail will tend to loosen the latter in 
the stone. 

Drivers. — There are several kinds of drivers for millstones. Many 
prefer the oscillating form, as it has some advantages when the spindle gets 
out of tram, which should never be allowed to occur. Rigid drivers have 
their advocates, and it is claimed for them that they keep the burrs in better 
face, not allowing them to get in wind, and make a more even granulation. 
They would work better, however, with gearing than with belts, as the belt 
presses the spindle too much to one side, and this pressure has a tendency 
to throw the spindle out of tram. 

The Dane Driver. — In one of the best drivers (Figs. 190, 191, 192), 
patented byjoseph C. Dane, Lacrosse, Wis., the spindle is made in the usual 
form, and is provided with a carrier pin passed through it near its upper end. 
Upon this the driver rests. The driver has a notch across the under edge of 
each side to fit over this pin. By this means the driver is carried around with 
the spindle as the latter revolves. The driver has jaws on opposite sides, 
lapping upon each arm of the bail, the bail being of the proper form to fit 
the eye of the burr-stone. The bail has a balance pin or cockhead passed 
down into an opening in the upper end of the spindle to the centre of the 
carrier pin. The end of the pin is pointed, and rests in a recess in the car- 
rier pin, thus making the point of suspension and drive in the same plane. 
The jaws of the driver are beveled off above and below the line of drive to 
allow the bail to work in the jaws without friction. To keep the driver level 
as it rests upon the carrier pin there are two pins inserted in the under side 
of the bail, projecting down to and nearly touching the driver, thus holding 
it to a level position. This gives an easy motion upon all points of the com- 
pass and a facile adjustment to the runner, so that it will present an even face 
to the bed-stone at all times, even when the spindle gets out of tram. 

By placing the point of suspension and the line of drive on the same 
plane, and that plane placed in the centre of weight of the stone, and having 
the stone well balanced, the stone will run steadier and present a more uni- 
form face to the body of the stone, and by its ease of oscillation it will re- 
lieve itself of any foreign matter, such as a nail or piece of wire, quicker and 
easier than any driver will that has the point of suspension above the line of 
drive, for in any of these there is more or less slip of the driver. Such a 
driver will admit of the stones running closer together without rubbmg, 
thereby grinding the flour more evenly and finer, and producing a better 
grade of flour. It ought to make more and better middlings from wheat on 
the first grinding and leave larger bran. With such a driver there should be 
no wabbling, rubbing, or pounding when starting or stopping the stone, 
thereby preventing wearing or scuffing of the skirts, saving much time and 
labor in dressing, and will run longer without dressing than with drivers that 



306 



MOUNTING THE BURRS. 



are not made on this principle of having the Hne of drive and the point of 
suspension in the same plane being placed nearly in the centre of the weight 
of the stone. 

One Dane driver of which we learn is stated to have been in constant use 
for nearly four years, wearing only sufficiently to show the bearing places. It 








P 









Fig. 190. — The Dane Bail and Driver. 



can be fitted to any old spindle now in use by fitting the bail and driver to a 
sleeve that will slip on the top and fit the old spindle. 

Equilibrium. — Even balance is of three kinds : stable, unstable or in- 
different. A balanced body is in indifferent equilibrium when it will remain 




Fig. 191. — Dane Driver. 

in any position in which it is placed, although it is free to turn. A well- 
balanced loose pulley or vertical burr on a horizontal shaft is in indifferent 
equilibrium. 

A balanced body is unstable equilibrium when it has a strong tendency to 




Fig. 192. — Dane Bail. 



assume some other position than the one in which it is balanced. Of this 
class, a lead pencil balanced on end or a whip on a man's nose. 

A body is in stable equilibrium when there is some one position which 
it will assume in preference to any other, as a horizontal millstone. 



BALANCING THE RUNNER. 



307 



Fig. 193 shows how stable equilibrium is given to scale beams, the knife 
edges which carry the pans being lower than the point of suspension of the 
whole beam. If they were on the same level the beam would be forever on 
the topple and it would never stand still. 

Fig. 194 shows why it is that the heavy side of a stone rises when the 




Fig. 193. — Stable Equilibrium. 

stone is in motion, although it is the lower side with the stone. The stone 
which hangs down when quiet tries to get as far away from the centre as pos- 
sible when made to rotate around an axis. This is the principle of the steanj- 
engine governor. 

Fig. 195 shows the balls in unstable equilibrium, and Fig. 196 shows the 



/\Q^K 



.Q^Kv^Boo f^CT {tSa, 




Fig. 194. 

balls in stable equilibrium, with the point of suspension upon the centre line 
of gravity. 

Balancing tlie Runner. — The runner should be balanced upon the 




rLBj- 



r 



r 

Fig. 195. — Unstable Equilibrium. 

pivot of the spindle. There are three kinds of balance — standing, running, 
and starting, although, perhaps, this last may be omitted. 

A stone is in standing balance if, when hung upon the spindle, it stands 

c 

Fig. 196. — Stable Equilibrium. 

the same when turned in any direction. But a stone may be in perfect stand- 
ing balance and in very bad running balance; and as the only usefulness of 
the balance stone is when it is running, it is more important to get the run- 
ning balance than the standing. 




308 



MOUNTING THE BURRS. 



As regards the height of the cockhead, the stone must be so suspended 
that a horizontal plane through the point of suspension will divide it into two 
parts of nearly equal weight, the under part being slightly heavier. If the 
upper part were the heavier the stone would be in unstable equilibrium. Al- 
though perfectly balanced if the upper and lower were exactly equal, yet it 
would be in indifferent equilibrium. 

To put it in stable equilibrium, it is necessary that there shall be a slight 
preponderance of weight in the lower half. 

Standing Balance seems often to be one of the greatest bugbears of 
the miller, and yet there is nothing about it to frighten any body or to cause 
him to lie awake at nights. Standing balance can be got and maintained very 
easily by having round the millstone a hoop of iron with a right-hand screw 
at one end, the other end being riveted to the burr after the proper length 
has been attained. The ends may then be joined. In order to tighten the 
hoop, the bolt joining the two ends may be turned very easily by means of 
a nail inserted in a hole drilled through the bolt. 

Fig. 197 shows very crudely how to correct the weight of a stone that 
wabbles much, by screwing on a piece of iron, g, as shown at e, on the oppo- 




FiG. 197.— Attaching a Balance Weight. 

site side from where the stone hangs down, within an inch or two of the face 
of the stone. If the spindle be in the centre of the stone, and the latter be out 
of balance, the trouble will most likely be a heavy block of burr on one 
side, as at a. 

Running Balance. — A stone may be in prefect standing balance, yet 
very much out of running balance. This is because it will be in standing 
balance if there is as much downward pull of gravity on one side of any 
vertical diametral plane as on the other, no matter whether or not there is 
equal mass or weight. In the matter of standing balance, one pound two 
feet from a central vertical plane has as much influence in causing a down- 
ward pull of gravity as two pounds one foot. 

The tilting influence of a weight in standing balance is measured by its 
mass (or weight) multiplied by its radial distance from the axis. When, 
however, it comes to running balance, the vertical action of terrestrial gravity, 
or mere weight, is largely superseded by that of the so-called centrifugal force, 
tending to throw the portions of a rotating body outward from the axis, 
no matter in what position that axis is, vertical, horizontal or inclined. 

Centrifugal Force. — The force or influence tending to throw a revolv- 
ing weight from its centre of revolution is measured by its weight, times 



RADIUS OF GYRATION— BALANCING. 309 

the square of its velocity, and divided by its distance from the centre of rota- 
tion. Expressed differently, it is equal to a force which would give the mass 
its stated velocity in a space equal to the diameter of the circle, because a re- 
volving body reverses its direction in going around the circle of revolution. 

Radius of Gyration. — In the case of the runner of an under-runner 
mill, which stone has no eye, but is a uniformly thick disc, the weight of 
the burr is supposed to be concentrated in a circle called the circle of 
gyration, the diameter of which is .707 times that of the diameter of the burr. 
The centrifugal force of a revolving disc, of uniform thickness, is got by 
multiplying the weight by the square of the velocity at the gyration circle in 
feet per second, and dividing by the radius of gyration in feet and by 32.2 ; 
or by multiplying the weight by the square of the number of revolutions per 
minute and by the radius of gyration in feet, and dividing by 2935. 

Thus, in a four-foot burr, the gyration circle has a diameter of 4 x .707 — 
2.828 feet, and a circumference of 2.828 x 3.1416 = 8.8844 feet. If it makes 
150 turns per minute, its rim speed is 150x8.8844=1332.6667 feet per 
minute, or 22.2111 feet per second. Supposing it to weigh 1,000 lbs., its 
centrifugal force will be, by the first rule, 

1000 X 22.211 1 X 22.2111 

= 10835. 1481 lbs. 

I. 1414 X ^2.2 

By the second rule, its centrifugal force will be 

1000 X 150 X 150 X 1. 414 « „^ Ti 

2 5 2_i = 10839.863 lbs. 

2935 

In the case of a flat rotating ring, such as a flat millstone of equal thick- 
ness, with an eye, the radius of gyration is rather more difficult to determine 
accurately, and we shall not consider it here. I have merely introduced the 
abstract subjects of centrifugal force and gyration to set the reader thinking, 
and to point out very markedly the difference in the forces acting in a stand- 
ing and in a running millstone. 

The centrifugal force of a homogeneous ring of rectangular section, rotat- 
ing on its centre, is equal to half the weight of the ring, times the square of 
the number of revolutions per minute, times the square root of the sum of 
the squares of the outer and inner radii, the whole divided by 2933.5 (^^ more 
roughly, by 2935, ^'^ i"^ ^^e former case). Put as a formula : 






2933-5 

The radius of gyration of such a body is equal to the square root of half the 
sura of the squares of the outer and inner radii, that is, to 



Balancing. — A burr that is in running balance at one speed will 
seldom be so at another speed ; consequently, it ought to be given running 
balance at the speed at which it is to be worked. 

It must be remembered that the tendency of a revolving weight is not to 
rise, and it is not to fall, but it is simply to get as far as possible from the 
axis. If the overweight is below the centre line, as in Fig. 179, or in the case 
of a millstone which has the point of suspension pretty well up above the cen- 



310 



MOUNTING THE BURRS. 



tre plane of gravity, it will tend to rise. This is the case with millstones, be- 
cause they are built below of solid burr, and in the upper portion of a lighter 
material ; but balancing weights put into the upper portion of the burr tend 
to throw that portion down when running, whereas the same weights, if put 
in the lower portion, would tend to throw it up. 

Fig. 198 shows a section of a burr through two blocks of unequal depth. 



Standing. 



Running. 




Fig. 198.— Tendency of the Heavy Side. 

While the burr stands the heavy block tends to keep that side down, but 
when running the heavy block tends to tip its side up. The wrong method 
of balance in this burr is shown in Fig. 199, in which the light weight, being on 
the heavy side, but pretty well toward the lower portion of the burr, tends to 
tip that side up. In Fig. 200 correct balancing is shown. 



Standing. 



Running, 




^'•li!. INC rl.T 



Fig. 199. — Wrong Arrangement. 



Putting in Running Balance. — The following is one plan for 
putting in a running balance : Take two boards of hard wood, one-fourth 
of an inch thick, eight inches wide, and about five feet long. Raise the 
runner and put these boards between the stones at a proper distance from the 
eye and skirt, and nail the ends of the boards to the floor. Set the stones 



p^ 






-1 


-pj 






M 


^i^ 




^» 


^^^^^^ 




Fig. 200. — Correct Balancing, either Standing or Running. 



running with as much weight on the boards as will allow it to run easy, yet 
resting firmly on the boards. Make a rest over the stone and turn off the 
top perfectly true from the eye lO six inches from the skirt, and then take 
out the boards. Now set the stone running at full speed, and, with a pencil 
at the rest, mark lightly where the stone is the highest. You can now use 
your judgment as to how much the stone runs out of balance or out of its 
plane surface, at a fair speed of 175 revolutions. After putting in lead in 
the light side, start up again and mark as before. The stone should be raised 
so as not to touch the bed-stone. 



PUTTING IN RUNNING BALANCE. 



311 



In balancing, if a heavy block was at the heavy side, as at a, Fig. 201, many 
millers would put the weight at B, to put it in standing balance ; but this 
would be wrong, as it would make the running balance that much Avorse. 

Fig. 202 illustrates what is called the "Common Sense" millstone balanc- 
ing device. The principle of this device is to load the stone even, and thus 
have running and standing balance at any speed. The cut shows two shot 
cups in each quarter of the stone, one above the cockeye and one below the 

B 




t* IG. 201. 



cockeye. These cups will hold about eight pounds of shot each, which is 
sufficient to overcome any surplus heft there may be on the opposite side. 
There is a screw with a big head through the band into the back side of the 
cup, which is removed to admit the shot, or to remove the shot should there 
be too many in the cup. These cups are accessible at any time. After find- 
ing the light place in the stone, remove the screw and put in shot until bal- 
anced. The cut represents half of the millstone, showing the location of four 
of the eight shot cups. If the stone is three pounds heavier at cup 2 than it 




■t\l' .,•>,- 

, • I I I I I , 
, / , I I • / ■ 




TT~7~7~7~SuS, 



Fig. 202. — Millstone Balancing Device. 



is at cup I, all other parts of the stone being of equal weight, the surplus 
weight is below the cockeye, and when standing still that side of the stone 
will drop down, being three pounds heavier than the opposite side ; but if the 
stone is run at 150 revolutions, the heavy side will incline upward the same 
as engine governor balls. Now, by putting three pounds of shot in cup i, 
there is just as much weight below the cockeye on one side as on the other. 
If there was a surplus of three pounds near cup 2, and of five pounds near 



312 MOUNTING THE BURRS. 

cup 3, the stone would be in a bad shape indeed, and with the usual means of 
balancing would cause a very tedious job ; but with the cups located as 
shown in the diagram, it is said to be very simple and easily done. Put five 
pounds in cup 4 and three pounds in cup i; now it is loaded evenly again, 
with the same result as before. Take still another case. Suppose there is 
three pounds surplus near cup 2 and three pounds near cup 4; in this case it 
would be in standing balance, but very much out of running balance, be- 
cause, when running, the surplus weight at cups 2 and 4 would incline to 
come on a level with the cockeye, or point of suspension ; but if three 
pounds of shot are put in cup 3 and three pounds in cup i, it will be loaded 
even again, and of course is in standing and running balance. To get a good 
running balance the weight must be equal on all sides of the cockeye, both 
above and below it. If there is a surplus weight on one side below the line 
of suspension, the same amount must be put on the opposite side below 
that line. 

Brown's method for obtaining running balance is to take two thin pieces 
of thin close-grained burr four inches long and six inches wide, plain gauge, 
and dress them down to about three-eighths of an inch thick throughout; 
raise the runner to half an inch clear of the bed, and slip these pieces be- 
tween, one on each side, and about half-way from the spindle to the outer 
edge ; slip a piece under each projecting end of these to fill the space be- 
tween them and the face, and drive a nail down through to keep them all 
firm. Now, start the stone and let it down until it scrapes upon the board, 
and, while it is fitting and flushing the surface of these fit a plank over the 
top of the stone in a convenient place for a rest, and turn the whole back off 
perfectly true. If the face is kept down tight to the boards the back will 
agree exactly with it. Now, stopping the stone, raise it up and remove the 
boards. When started again at working speed and clear of the bed, it will 
take its regular running position, and its light side may be marked by hold- 
ing a lead pencil against the raised plank and moving it carefully down until 
it touches the new-turned back. Stopping the stone, dig out a portion of the 
plaster next the hook on the marked side and run in some lead. Start and 
test again, and continue this until the pencil marks equally all around the 
back. As long as the motion is kept up the stone will run exactly true, and 
when the motion subsides one end of the stone will drag unless the stone is 
also on the true standing balance, which is unlikely. 

To get the standing balance without disturbing the running raise the run- 
ner, and with a hand on each side move it each way until it is clear of the 
driver and free to balance every way around the pivot ; now try it all 
around to find the light side, and weight that side until it balances alike. 
Mark the side across the hook, turn the stone on edge with that side up, and 
measure the distance from the face of the stone to the pivot-socket in the 
bail ; then measure the same distance from the face on the edge of the stone, 
and mark that on the hook ; the intersection of these two marks will show 
the centre spot where the lead should be put in theoretically. Practically, 
run the weight in two inches below this point, because the force is applied 
below the point of suspension about four inches. 



POINT OF SUSPENSION. 



313 



Point of Suspension. — Fig. 203 shows four different kinds of points 
of suspension. The sharp point, No. i, is the most sensitive, but would 
very soon get banged up, which would alter its level and the balance. 
Rounding it, as in No. 2, it is still subject to the same objection. If it is flat 
on top, the centre bar is apt to ride, so that the half-circular top, No. 3, or 
I 2 " 4 







Fig. 203. — Methods of Suspension. 

the perfect globe, No. 4, offers the best kind of a point of suspension, being 
easy to make and keep in true, and not liable to be damaged. 

One common fault with some universal driving irons is that the four trun- 
nions are not exactly on the same level. If there are two points of suspension 
or centres of oscillation on two different levels, B and C, Fig. 204, it will be 
very difficult or even impossible to properly balance a stone so hung. 

To W. E. Sergeant, of Minneapolis, we are indebted for some very 
practical directions for ascertaining the centre plane of gravity and deter- 



^ 



M 



N 



I lotuwoaswtss (rs. N-Y 




i^ 




B 
C 



\jXrWi9«Ttt.^ 



IhSR^J----' 



& 



I"iG. 204. — Forms of Driving Irons. 



mining the point of suspension of a millstone. If the volume of the blocks 
composing this burr were known and the weight of each, it would be a 
somewhat difficult mathematical calculation to determine where this central 
plane of gravity lay ; but as it is we have no knowledge of the materials 



314 



MOUNTING THE BURRS. 



which enter into the construction of this composite body, and some prac- 
tical test must be applied, without special machinery, to find this central 
plane. Many complicated methods could be devised. We think that few 




Fig. j^i. Li.Y.MSEL. 



could be more simple and practical than the following : Plumb a post in the 
mill ; be sure that it is not approximately but absolutely plumb. Roll the 
burr up against it so that its face shall lie up against and alongside of the 



S 




KiG. 206. — Damsel. 



plumbed post. Take a large three-cornered file or a similar balancing edge 
in front of the plumbed face and parallel with it, at a little less distance from 
the post than half the thickness of the burr. Roll the burr upon this file and 




Fig. 207. — Damsel. 

note where it leans toward and from the post. By rolling it off the file and 
trying new balancing points from time to time some new balancing points 
will be found. One point will be found at which the burr does not tend to 




Fig. 208. — Silent Feed. 



lean either toward or from the post. This point being founds the plane which 
passes through this and parallel with the face of the burr will divide it into 



THE DAMSEL— FEEDERS. 



315 



two portions of unequal height but of equal weight. The point of suspension 
should be made about a quarter of an inch above this plane. 

The Damsel. — The damsel is shown in Fig. 205 in one form, and in 
Fig. 206 in another. Fig. 207 is another form of damsel. 




Fig. 209. — Silent Feed, 

Feeders. — Flour middlings and meal are difficult to feed with regu- 
larity, because they have a choking tendency. To prevent choking, and to 
insure regular feed, it is sometimes necessary to have a positive mechanical 
feeder. A'loose rod of wood in the eye, extending up into the hopper, often 




Fig. 210. — Silent Feed. 



serves to keep loose choky material from clogging, as it rotates and stirs the 
stream. 

Fig. 208 shows a silent feed, in which the regulation is effected by 
means of bevel gears. Figs. 209 and 210 show other forms of silent feed. 

21 



316 



MOUNTING THE BURRS. 



In the silent feeder the grain is admitted from the bin or stock hopper 
through a pipe open at both ends, the lower end being in close proximity to 
the saucer on top of the rynd, the speed being regulated by a small hand- 
wheel, which being turned to the right or the left raises and lowers a small 
pin by which the opening between the mouth of the feed-pipe and the saucer 




Fig. 211. — Lighter Screw. 

will be increased or diminished. Sometimes the feeding pipe is fastened on 
the curb by a tripod. It feeds more regularly than the damsel (or dansil). 

The damsel, while it is certainly an improvement over the clapper and 
shoe, makes a great deal of noise, and is otherwise inconvenient. 

Autoraatic Stone Lift. — This consists of a cord having on it a series 
of leather discs and suspended in the hopper. This cord passes over several 
pulleys, and is attached to a weighted lever, one end of which has a ratchet 
tooth engaging with a wheel on the same axis as a drum around which passes 




Fig. 212.— Crane Irons. 



a chain pulling upon the lighter rod. A cord passing around the wheel 
carries a weight sufficient to lift the stone. As long as the stream of wheat 
keeps running, the hopper, the pulley, and the leather discs keep the tooth 
lever engaged with the ratchet ; but when the feed stops the lever is de- 



FITTING A NEW BACK. 317 

tached and the weight lifts the stone free and clear so that it cannot destroy 
its face. 

Fig. 211 shows the ordinary form of lighter screw. 

Iron Burr Crane.— In place of the ordinary burr crane of wood, we 
recommend the light and strong portable iron device shown in Fig. 212, 
made by the Richmond City Mill Works, Richmond, Indiana. These hoist- 
ing irons are well proportioned, strong and durable. The screw is made of 
the best wrought iron, and the bales and wrench are of malleable iron. 

Oiling Mill Spindles. — The plan of putting a string around the 
spindle has the disadvantage that there is danger of having to take up the 
mill to put in a supply of tallow or oil. A better way is to guide oil through 
a small pipe from the outside of the curb down below the husk frame and 
bottom stone, thence with an elbow toward the bush, just below the bush ; 
thence through a hole or opening in the bush upward to nearly a level with 
the top of the bush, where a groove is cut just deep enough to admit the dis- 
charge end of the little pipe to sink below or even with the level of the top 
of the bush, and not be in the way of anything which might be used as a 
bush cover to keep out dirt and trash. 

Fitting a Nevf Back. — When the back breaks and flies off in run- 
ning, or the stone is not heavy enough, a new back must be made. To do 
this, block the stone up, face downward, evenly, solidly and perfectly leveL 

Pick and scrape off the plaster down to the face blocks. Wash these 
and soak them well with water. 

Daring this time have some clean bits of burrstone soaking. 

Mix plaster-of-paris with clean water and a slight proportion of glue. 
Pour this upon the dampened stone back and rub in with the hand. 

Place small spalls over the joints of the blocks with a stiffer plaster. 
Build around the eye and verge walls of burrstone, four and five inches 
high. To make the stone heavy, take small pieces of iron, well washed and 
free from rust or grease, lay them evenly around the stone between these 
walls, and pour in thin plaster until the surface is nearly level with the two 
walls. 

If the stones do not need weighting, use burr-spalls instead of iron. 

Keep on building the walls until they are within two inches of the thick- 
ness your stones are to be, keeping the eye wall two inches above that 
around the verge. Fill in the space with stones, pour in plaster nearly level 
with the walls, and leaving a rough surface. 

When this has dried and perfectly set, rest the stone on the edge and 
plaster around the edge. When thus cased, lay the stone on the cockhead 
with the driver off, rest the spindle and balance the stone. Have a tin made 
the size and reaching to the proper height the stone is to be at the eye. 
Fasten this down. Fasten a hoop of wood or iron around the verge so as to 
reach up to the desired height at the verge. 

Within this hoop and the cracks around it, pour in thin plaster with 
plenty of glue water, which will retard the setting, and, with straight-edge 
resting on the hoop and the tin, and working the plaster with a trowel, turn 
the stone. Make the surface of the back even and smooth. Take off the 



318 MOUNTING THE BURRS. 

hoop and smooth the back and edges. Lower the spindle till the runner lies 
solid. Heat the iron band or hoop, put it on and cool it with water. The 
best plaster-of-paris must be used. Many prefer the use of sulphur (brim- 
stone) to lead, as it is not poisonous. 

In backing up millstones, or in making a new back, trouble is sometimes 
experienced by the very short time that elapsed before the whole back sets fast 
and hard. To prevent the plaster from setting too fast, it should be mixed 
with glue- or with isinglass, or, if this is not at hand, with milk. We have not 
tried glycerine, but think that it would retard the drying. Mixing the plaster 
with urine instead of with water answers. Alum in the plaster makes it finish 
close and hard. 

Cost of Building Up. — The cost of building up is considerable. It 
is considered good work to set two blocks a day. Averaging fourteen blocks 
to a stone, it will take a man nine days to do the work well. 

Allowing eighteen dollars ($i8) a week to the builder, the building of one 
stone would cost twenly-seven dollars ($27). 

The block dresser, getting two dollars a day, can dress four in a day, 
making seven dollars more. Hoops and plaster in backing up, together with 
labor, will cost five dollars, and labor eight dollars. Facing and furrowing 
would cost about twenty-five dollars ; making in all seventy-two dollars for 
building and finishing one millstone. 






CHAPTER XXIV. 

VARIOUS MILLSTONE DRESSES. 

The Dress —Choice of Dress— Path of Material— Elements of Dress— Eye— Bosom — Face — Proportion 
of Land and Furrows— Duties of Furrows— Number of Quarters— Number of Furrows — 
Outline of Furrows! — Circle Furrow — HoUandish Circle Dress — Improved Circle Dress — 
Logarithmic Spiral Dress— Angle of Furrow Crossing — Laying Out Circle Furrows — Direction 
of Furrows — Draft— Depth of Furrows— Furrow Section— Smoothness of Lands and Furrows — 
Old Quarter Dress — The Hughes Dress — Compromise Dress — Pennsylvania and New Jersey 
Dress — Old Style Equalizing Dress — New Style Equalizing Dress — Combination Dress— Dickson 
Dress — Southern Dress — Jones Dress — Bowman Dress — Arndt's Dress — Ward's Millstone 
Formula — Dressing for Regrinding — Other Dresses (for Old and New Process, for Middlings, 
for Corn, for Wheat, &c.) 

Th.e Dress. — Milling being as yet so much more of an art than a 
science, no definite rule based upon scientific principles can be laid down to 
determine the exact dress which can be given for working the various kinds 
of material and turning out the various products which come within the pro- 
vince of modern milling. 

Upon no part of the work in the modern mill does the quality and cost 
of product so materially depend as upon the dress of the burrs, where burrs 
are used. 

While we cannot give definite rules for each particular case, we can lay 
down what is the average and recommended custom of skilled millers, which 
will do excellently well for others to follow until exact rules are determined 
and the art of millstone dressing elevated to a science. One thing is certain 
— no matter what quality of face, what amount of bosom, what draft or sec- 
tion of furrows is employed, the work must be perfect of its kind. The 
implements employed, and the methods of using them, will be separately 
treated in another chapter. In this chapter we shall consider the various 
elements which enter into the millstone dress, without regard to the manner 
of dressing. 

In the preparation of this chapter the author has relied very largely upon 
the opinions and experience of successful millers in all sections of this 
country and Europe. This being the case, he has largely quoted from their 
letters or published remarks without attempting to reconcile apparent dis- 
crepancies or contradictions ; because, in this as in many other instances 
where opinions apparently differ, the variance of unobserved or unrecorded 
conditions would account for much diversity of successful practice. 

The author has simply undertaken to lay down certain principles upon 
which careful and intelligent observation may be based and recorded. 

Choice of Dress. — The stone maker or miller must keep constantly 
in sight two things : First, the conditions that must be fulfilled by a perfect 
dress, and, second, the factors to be considered in order to obtain the desired 
conditions. 



320 VARIOUS MILLSTONE DRESSES. 

Referring to the first element, the quantity of the grain at the eye must be 
proportional to the exit of meal at the skirt ; and during the comminuting 
process, the grain must not be rubbed nor crushed, but cut. Under the second 
head we have to consider first which way the stone runs; second, its diameter; 
third, its peripheral speed ; fourth, the structure and material of the stones ; 
fifth, the nature of the material to be ground ; sixth, the method of milling 
employed. 

It is comparatively easy to determine what conditions a proper dress 
should fulfil, but it is a much more difficult task to describe how these con- 
ditions may be attained. The direction of motion is, of course, regulated by 
the buyer, and gives no trouble, but it would be by the merest chance that 
the burr maker could dress a stone that would perfectly fulfil the latter four 
conditions. The question might be asked, is there any one universal dressing 
which under all circumstances would satisfy all conditions? Plenty of millers 
have offered dresses which are calculated to grind anything under almost any 
condition, but the eagerness of mill-owners in taking them out generally 
comes fully up to the zeal with which their originators offer them. To many, 
if not to most millers, it will have happened in practice that two pairs of 
burrs, equal in size, dressed alike, apparently identical in quality and material, 
and running at the same speed, gave entirely different results, although hand- 
ling grists of the same grain. Although the distance of the stones may be 
the same, one may grind soft and the other hard. A moment's reflection 
on this point should satisfy the miller that there can be no one dressing for 
all conditions. In many cases mill furnishers have had burrs returned to 
them as of inferior quality when the fault was not in the quality of the stone, 
but in the dressing. 

There are some combination dresses, good for fair work with almost any 
material or work that may be demanded in any one mill ; but as good work 
cannot be done in this way, as by noting what will be most required and 
giving the dress specially adapted for those conditions. 

We advise our readers to draw the various millstone dresses in circles 
about six inches in diameter, one on card-board and the other on transparent 
linen or paper, and reversing the latter and sticking a pin through the centre 
of both, note the crossing of- the furrows. If this does not convince them 
that the ordinary quarter dress, with the parallel furrows, is imperfect, 
especially with few quarters on large stones, it will at least set them 
thinking. 

Path, of the Material. — The path of the material is different in under- 
runners from what it is in upper-runners, and different in vertical mills from 
either. In the first case the material falls on a "live" surface; in the 
second, on a motionless one ; in the third, on neither, strictly speaking. 

In the upper-runner the path, if the furrows did not change it, is stated 
by Kick to be a spiral ; in the under-runner, the involute of a circle. 

In Fig. 213 the lines A and B represent the supposed paths of the 
material on an upper-runner, as traced out by two noted British millers. 
They are widely different, and yet the probability is that each is very nearly 
right, for the conditions which its maker had in mind. 



ELEMENTS OF THE DRESS, ETC. 



321 



"In under-runners the path made upon the upper, or stationary stone, 
will be according to the involute of the curve r = ^^°Jf^^, ;" c being the 
friction coefficient, r = 0.16 inches = 6.3 inches, g = 9.088 metres = 29! 
feet. — (Kick.) 

Elements of the Dress. — These are the eye, bosom, and grinding 
surface or face proper ; the latter being divided into land and furrow ; and 
the furrows varying in duties, arrangement, number, outline, direction, 
length, draft, width, depth, section, and surface. 




Fig. 213. — Supposed Path of Material. 

Eye. — The eye is strictly an element in the dress, because it offsets or 
modifies the action of the furrows. The larger the eye and the greater its 
" flare" or taper downward and outward, the easier the feed and the less 
bosom and draft necessary. 

Bosom. — The bosom is for the double purpose of allowing the feed easy 
entrance and of giving the grinding or granulating face of the burrs a 
gradual action on the material being reduced or otherwise operated upon. 
The circumference of the eye being so much less than that of the skirt, the 




Fig. 214. — Section of Burr. 

stones must have a greater distance between them at the eye than at the 
skirt, in order to give the same annular area or channel for the material to 
pass in. The area and the depth of bosom vary greatly. The author 
believes that a wide, very shallow, perfectly even bosom, with well dressed 
surface, will be found advantageous in almost all styles of milling ; the 
furrows extending into the bosom. 

" In olden times the bosom was very much used. Afterward the number 
of quarters and leading furrows was increased, and the short furrows cut 



322 



VARIOUS MILLSTONE DRESSES. 



through into the leaders, which, of course, increased the draft, and the bosom 
has been reduced to the thickness of a sheet of paper." 

The Face. — The face or plane granulating surface proper, may com- 
prise nearly or all the area of the stone from eye to skirt ; or it may be a mere 
strip next the skirt. It may be furrowed or not ; generally the former. 

Proportion of Land to Furro-ws. — We have before us an account 
of a German miller, who, on finding that his stones would heat, reduced the 
breadth of the grinding surface from 25-132 of the diameter of the stone 
to 24-132, then gradually to 20, and the smaller the direct grinding surface, 
the better the results until he went below 20 to 18 or 19, which gave worse 
results, 20 giving the best. In the first case the temperature was 25° to 30° 
Reaumur = 88i° Fahrenheit to 99^° Fahrenheit. With 20-132 land it was 
only 8° to 10° Reaumur = 50° to 54-2-° Fahrenheit, and the capacity was in- 
creased 80 centners more per day." 

" The rule two-third furrow surface to one-third land surface is good for 
close stone and hard wheat. An open stone will stand more land, and soft 
wheat more even furrows." 

" Too much face cuts up the bran and causes specky flour. Too sharp 
or too rough a stone will do the same thing. When there is too much face 
the material may be ground two or three times before it leaves the stone." 




Fig. 215 — Grain of Wheat in Furrows. 

" One reason for change in millstone dress may be the increased power 
now applied and greater capacity for each run. The size of the burrs has 
been very much reduced. Whereas stones used to be from four and one-half 
to six feet in diameter, they are now from four and a-half down. More 
being required in a stone, of course less of it can be used in bosom." 

" The capacity of burrs depends, not on their diameter, but on their 
superficial feet of face. In order to grind a given quantity with large stones, 
fewer revolutions will be needed and a larger driving pulley required, while 
small stones of half the superficial face do the same work as large ones with 
twice as many revolutions and half the purchase. They have the disadvan- 
tage of having to do the same amount of work on half the surface, so that 
their advantage resolves itself down into their decreased cost and space and 
handling." 

Duties of the Furrows. — Here opinions differ. If furrows did 
nothing but admit air to the burrs, it would be cheaper to drill holes through 
the burrs, and then there would never be any furrow dressing required. 
They certainly perform at least four offices: granulation, cooling, distributing 
the chop between the faces, and carrying out; but their action is very 
different from what is generally understood concerning them. In proof that 



NUMBER OF QUARTERS. 323 

they are not essential, stones are run (though rarely) without furrows, and the 
granulation, distribution and carrying out have not been stopped, though 
the chop was unduly warm ; and in regard to the carrying out by " shears- 
like action," tests have been made with the furrows reversed, and not 
greatly affecting the capacity of the burrs. 

In order to show that the furrows do not perform all the office of 
distribution or carrying out, we may refer to some experiments made by 
Schmidt, in which the runner was reversed, there being no great difference 
in the resulting material. Hlavac made some tests with a burr-stone i.i metre 
= 43.30 inches in diameter, having twelve quarters ; the draft circle being 
8 centimetres = 3.1496 inches in diameter, and there being two short 
furrows in each quarter. The eye was 26 centimetres = 10.2362 inches in 
diameter, and the breadth of the proper grinding face was 19 centimetres = 
7.4803 inches. 

The furrow section and the bosom when right, and the balance perfect. 
In the upper stone were three wind furrows. With 300 litres of ended wheat 
(Hochschrot) product making the first reduction was, with the runner 
turned in the proper direction 12^ x 5-5 kg. of break flour of different kinds, 
in all 19.5 kg. = about 6 per cent.; 10.2 kg. of fine middlings, 22.8 per cent. 
of coarse middlings; the temperature of the chop being 23° C. = 73.4° F. 
With the runner reversed in motion, the quantities of break flour of three 
grades was 17.3 and 5.8, in all 25.8 kg.,= about 8 per cent.; there were 8.8 
per cent, of fine middlings and 30 per cent, of coarse middlings ; the tem- 
perature of the chop being 25° to 26° C. = 77° to 78.8° F. 

This shows that while the ordinary run of burrs will do different work 
with the furrows reversed than with them running in proper direction, and 
there will possibly be more break flour, the influence of the furrows is not so 
important as is ordinarily supposed. 

Number of Quarters. — As regards the number of quarters and the 
number of short furrows in each, we have a standard which can be main- 
tained that for good dressing the essentials are to have many principal 
furrows, few secondaries and a great number of quarters. It is very seldom 
that we find more than three or less than two short furrows in each quarter ; 
but it should be different. We often see sketches and plans of dresses with 
five secondaries and one leader, that is, six furrows to the quarter, making 
it appeaf as though there were more room on a little strip of paper than on 
a large stone. Now, why should there be many quarters with few secondaries 
rather than few quarters with many furrows ? If we take a dress of ten 
quarters, each having one leader and five secondaries, the secondaries lying 
parallel with the leaders, it is clear that each of the short furrows has a 
separate draft circle. Now the angle of intersection of furrows depends 
altogether upon the diameter of the draft circle, so it is not difficult to 
comprehend that the intersecting angle of the shortest secondaries must be 
the most obtuse, and that of the longest secondary the most acute. The 
principal objection to this style of dress is that the draft circle of the outer 
secondary fails to fall into the grinding surface of the stone, so that the grist 
must be drawn far out without reduction. 



324 VARIOUS MILLSTONE DRESSES. 

Many experienced millers say that two furrows in each quarter is the 
proper number, and this independent of speed, diameter, or material of the 
stone or the nature of the grist. 

A porous stone does not need so many furrows as a close new stock 
burr. 

The more quarters the more even the draft of the furrows will be, one 
with the other. There is little or no use in having one furrow with four-inch 
draft and another with ten to twelve. Yet there is this to be said, that if 
there be too many furrows running directly from the eye, they will be apt to 
chop the bran up too much. This, however, can be remedied by bosoming. 
There is this advantage in having more furrows in the skirt, that there the 
speed and friction are greater, and more cooling surface is needed. 

Our own opinion is that the " quarter dress " proper is a barbarism, as 
generally applied ; and that when we consider the course of the grain or 
other material, in its outward progress from eye to skirt, we must incline to 
such dresses as will give all the furrows on each stone, as far as possible, the 
same draft : this entirely independent of the question as to whether or not 
the angle of crossing of bed and runner furrows shall be the same for all 
points along the length of the furrow. The " quarter dress " may be 
abolished and still leave free choice between straight, bent or curved 
furrows ; between furrows all of a length and those of varying length ; 
between those having the same crossing angle* all the way out, and those 
having the crossing angle vary at different distances from the eye. 

The writer's objections to the quarter dress are based on analogy. Evi- 
dently the fewer quarters the greater the disproportion between the draft of 
the leaders and that of the secondaries, in stones of equal diameters. 

Number of Furrows. — Evidently a given area in furrows may be got 
by having few wide furrows, or more narrow ones of proportionate width; 
by a few long furrows, or more short ones of proportionate length. Here 
again the questions of stone diameter, material operated on, and product 
desired, come in, complicated with details concerning the methods of 
"ventilating" the stone, and the bosom, hardness and porosity of the stone. 
Modern tendency seems to be to an increase in the number. 

Outline of Furrows. —Furrows may be circular, rectilinear, bent, or 
spiral; "The first form has great drawbacks, and must yield before the 
widely-extended straight furrows, and the last is complicated and has not 
at the present time secured a reception. Beyond the question of whether 
the furrows shall be circular, straight or spiral, comes the question of leaders 
and secondaries. The secondary furrows must be either tangential to the 
same draft circle as the leaders, or parallel with the .leaders themselves. 
The value of the secondaries is in no sense inferior to that of the leaders. 
Secondaries parallel to the leaders are much more common than those strik- 
ing from the same draft circle. But to discuss which mode is the best of the 
two is a rather difficult matter." 

*" Crossing angle" means the angle formed by any furrow in one stone, with one in the 
opposite stone. With curved furrows the angle is measured between the tangents at the point of 
crossing. 



OUTLINES OF FURROWS. 



325 



"A^curved dress requires more power to drive the stones than a straight 
one. As regards curved dress, the skirt wears lower than the breast, and the 
heat caused by the great pressure affects the quality of the flour. These 
figures refer to a4^-foot stone of close texture, running one hundred and fifty 
or one hundred and sixty," 




Fig. 2i6. — Bent Furrow. 



It is hard to discuss the outline of furrows without going very extensively 
into the question of draft ; because straight furrows (unless radial, a rare 
form) invariably have a greater crossing angle at the skirt than at the eye ; 
furrows which have the arc of a circle as an outline may have either an in- 
creasing or a decreasing crossing angle, according as they are laid out ; and 





Fig. 217. — Straight Quarter Dress. 



Fig. 218.— Circle Quarter Dress. 



the peculiarity of the so-called "spiral" furrow (generally a "logarithmic 
spiral ") is that the crossing angle is the same all the way along its length. 

It may be said, however, in general terms that the straight furrow is the 
most common and the easiest laid down and put in, while the logarithmic 



326 



VARIOUS MILLSTONE DRESSES. 



spiral is the most difficult to design and to make. Under the head of special 
dresses, furrows of various outlines will be discussed in detail and illustrated. 
Circle Furrow. — The " circle furrow " has one or both edges a true 
circular arc. It is sometimes incorrectly called the " Sickle Dress;" but this 
latter term should correctly be applied to a curved furrow having varying 
curvature. The circle furrow may be varied by the proportion which 
its radius bears to the semi-diameter of the stone, and by the distance between 
the centre of the stone and the centre from which the furrow is struck. 




Fig. 219. — Logarithmic Spiral Dress. 

The longer the radius of the furrow circle, the nearer it approaches in 
its action to a straight furrow, and the more the crossing angle increases 
as we near the skirt. 

The greater the distance between the centre of the stone and the centre 
from which the furrow circle is struck, the less the crossing angle at any 
given point, and the less the increase of the crossing angle as we go from 
eye to skirt. 

It is desirable in circle dresses to have the crossing angle as great as 
possible, especially at the eye, to facilitate the feed. 



HOLLANDISH CIRCLE DRESS, ETC. 



327 



HoUandish. Circle Dress. — This dress has no quarters ; all of the 
furrows are alike ; the circle radius is from f to f the semi-diameter of the 
stone, and the furrow circle starts at the centre of the stone. The crossing 
angle at the skirt is 77° where the furrow radius is f that of the stone, and 69° 
where it is \ the stone radius. 

Improved Circle Dress. — An improved circle dress having all the 
furrows alike has the furrow radius 0.633 that of the stone radius, and the 
distance of the centres from which the furrow is struck is 0.62 the stone 
radius. This gives a crossing angle of 110° at the skirt. With furrow radius 




Fig. 220. — Furrows with Equal Draft. 

of 0.76 the stone radius and distance from stone centre to centres of furrows 
of -^ the stone radius, the maximum crossing angle is 86°. 

Logarithmic Spiral Dress. — This has the crossing angle constant 
all the way out, and generally all the furrows are alike in length as well as in 
curvature. To construct it, mark out a number of close and equi-distant 
radii, and having laid out a furrow line from one, with the desired draft, 
measure the angle between this and the radius it starts at, and then, where 
it cuts the second radius, make a second line (having more draft) which has 
the same angle with the second radius. In this way proceed, and then 
modify the broken line into a curve. 



328 



VARIOUS MILLSTONE DRESSES. 



Fig. 219 shows logarithmic spiral furrows of three different drafts. The 
furrows A make a constant angle of 15° with every radius ; those at B, 30°, 
and those at C, 45°. There are no parallel furrows ; all of a kind have the 
same draft. 

Angle of Furrow Crossing. — The various kinds of dresses may be 
divided into the following classes : (i.) Those in which the angle of furrow 




Fig. 221. — Quarter Dress — Wrong Arrangement of Short Furrows. 

crossing increases toward the skirt ; in other words, the draft of the outer 
portion of the curve is greater than that of the inner. In these we may class 
the old circle dress and the improved old circle dress. (2.) Dress with a 
constant crossing angle. In this we include the logarithmic spiral dress 
(Fig. 219). (3.) Those in which the angle of furrow diminishes toward 




Fig. 222. — Evans Dress. 

the skirt. In this class we find all straight furrows, the furrows of the new 
circle dress, and the Evans dress. See Fig. 222. 

Old " quarter dresses " divide themselves into two groups — those hav- 
ing all the furrows of the same draft, and those having greater draft for 



ANGLE OF FURROW CROSSING. 



329 



the short furrows than for the leaders. In Fig. 220 there is shown a quarter 
dress, in which the skirt furrows have the same draft as the leaders. 
Those in which the short furrows are parallel to the leaders are illustrated in 
Figs. 217, 221, &c. It must be noted that the short furrows must never be 
prolonged into the next quarter or leader. 




I u m IV 

Fig. 223. — Wiebe's Dress. 



The Evans Dress, Fig. 222, is a curved dress in which the leaders have 
greater draft toward the skirt than at the eye — the short furrow being 
parallel to these. In Wiebe's Dress, Fig. 223, the leaders are curved and 
have increasing draft ; but the short furrows are curved exactly like the 




Fig. 224. — New Circle Dress. 

leaders, except that they are not prolonged in the eye. In the new circle 
dress. Fig. 224, the draught diminishes toward the skirt instead of increasing. 
All the above-named dressers are for upper-runners, and then we have (4) 
dresses for under-runners. 



330 



VARIOUS MILLSTONE DRESSES. 



In any circular dress in which the radius of the furrow is equal to the 
distance of the middle point of the furrow from the centre of the stone, the 
sine of half the angle of crossing of the furrows is equal to the radius vector, 
and the crossing angle increases toward the skirt. 

The angle of furrow crossing can be smaller with under than with upper 
runners ; large crossing angle not being required at the eye, in order to 
permit the feed to enter easily and rapidly. The furrows of an under-runner 
should make an angle at each point, with the path of the chop, greater than 
the friction angle of the material (which is about 37°), the sides of the 
furrow being steep. If this is not observed a large part of the material will 
be unbroken. Where the furrow has a perfect feather-edge, the material 




Fig. 225.— Crossing of Furrows. 

will follow most nearly the true involute path. The old circle dress should 
in no case be employed for under-runners. 

Schmidt announces that the distribution of the chop by the working 
together of the furrows, tracing the material from the eye toward the skirt, 
is of considerable consequence, and announces that two curving furrows, 
which working together must never cross each other in two points at once. 
He explains these by diagrams, which we reproduce here. Referring to 
Fig. 225, A B is a curved furrow in the bed-stone (we speak of upper-runners 
now), and C D, shown in dots, represents the furrow in the upper stone or 



ANGLE OF FURROW CROSSING. 



331 



runner ; the arrow, showing the direction of motion of the dotted furrow 
line, C D. It will be seen that these cross at the point O. There are two 
tendencies for the pass of grain : one to go toward P by the action of the 
furrow of the runner, and the other to go toward P by the action of the 
furrow in the bed-stone. Referring to Fig. 226, where the letters are the same 
for similar things, the line/ is the average or resultant between the force X, 
perpendicular to A B, and the force y, tangent to A B. In order that 
distribution or carrying out by the furrows may take place, it will be 
necessary that jv shall be in the direction of the skirt, which will not be the 
case when the curves cross each other in two places, as shown in Fig. 227. 
The angle to f, made by the tangent to the two curved furrows, is the crossing 
angle of those two furrows at that point. The pressure x, multiplied by the 




Fig. 226. — Ckossing of Furrows. 

coefficient of friction of the chop upon the stone, will give the power 

required to carry the chop out to y. Where the distance y is equal to x 

times the coefficient of friction, then both the forces, x and y, will have 

equal force, and there will be no crowding of the particles in the direction 7. 

Schmidt then says that for a given angle of crossing of the furrows, the 

tangent of angle is equal to the coefficient of friction of the chop upon 

the stone (this angle will be called the friction angle) ; there will be no 

distribution by the furrows, y being equal to x times the coefficient of 

friction. If the crossing angle of the furrows becomes greater, then this 

force y will increase and x will be less. This will give a general rule 

concerning the distribution of the chop by means of the furrow alone, that 

the greater the angle of crossing of the furrows, the greater their action in 

the distribution of the chop. 

22 



332 



VARIOUS MILLSTONE DRESSES. 



Where the angle of crossing is less than the friction angle, then the 
furrows will not act to distribute or push out the chop, but only to cut 
or break the material. Schmidt concludes that for the distribution of 
the chop by the crossing of the furrows the crossing angle of the furrows 




Fig. 227. — Wrong Furrow Crossing. 

must be double the friction angle. The friction angle of the chop upon the 
stone face is about 37° to 38°; and this would point to a crossing angle for 
the furrows, of about 75°. But the experiments already quoted, of the 
runner working backward without much affecting the quantity of the chop, 








- - ri 






Fig. 228. — Laying Out Circle Furrows. 

show that the influence of the furrows in carrying out the chop by their 
working together is of very little importance ; this being due more to the 
centrifugal force and the ventilating action of the furrows than to the shear- 
ing action of the furrows. 



LAYING OUT FURROWS— DRAFT. 333 

Laying Out Circle Furrows. — In laying out circle furrows the 
lengths OC, CM must be considered. In one dress recommended, where R 
represents the stone radius, say i, n the furrow radius, is -^2" = 1.414, and 
ra, the distance OC of the stone centre O from the centre C the furrow is 
struck from, is -y/S = t-732- See Fig. 228. 

Direction of Furrows. — " To prevent short furrows running the 
wrong way, the following rule must be observed : All of the short furrows in 
a quarter must lie not behind the leader, but invariably before the leader 
belonging to that quarter. 

The advertisement of the French stock company of the Bois de la Barre, 
in La Ferte-sous-Jouarre, appearing in every number of the Deutschen Miihl- 
anzeiger, attracts attention from the fact that the illustration — a dressed burr 
— shows the fields with the furrows running the wrong way. Of course, we 
cannot say that this firm would reverse the short furrows in this way on the 
real stone, still it must cause astonishment that such an important millstone • 
factory should employ an incorrect picture. Even mill architect Haase, of 
Breslau, in his work on practical milling, shows a dress very much like a 
reverse one ; he calls it the Felderwischsch&rfe, but I never heard of any mill 
employing it." 

Draft. — When it comes to the question of dress you will find that more 
millers give one inch draft to the foot diameter than any other draft ; and 
they are very particular about this one inch draft to the foot. It does not seem 
to make much difference if there is a feather-edge or a step, a smooth or a 
rough surface, or what the depth is, or why the angle should be rounded or 
not, but they stick to the one-inch draft for any or all conditions, no matter 
if the speed is as low as one hundred and twenty-five or as high as two 
hundred to the minute. 

Both the centrifugal force and the air current are greater in the case of 
fast running burrs than in slow ; so in the latter case there must be more 
draft than in the former. The draft may be corrected somewhat by the 
depth ; if too slight, the furrows may be deepened, if too great let them 
become shallower. 

Open porous stones require less draft and fewer quarters, because care 
must be taken to give them plenty of face. Hughes' rule for draft is, for the 
straight dress in close stone, an inch to the foot of diameter ; for curved 
dress three-fourths of an inch. The dress should be such that in grinding 
the stone should receive a proportionate quantity on its entire surface from 
the eye to the skirt. In obtaining this we encounter this difficulty, that the 
circular motion increases from the eye to the skirt. It is an important ques- 
tion, and more so to mills of light power than to those with plenty. It is to 
meet this question of varying speed from eye to skirt that curved dresses 
have been devised. 

The dress that will suit 150 revolutions will not suit 175. One inch 
draft to the foot diameter is a common rule, but this must be deviated 
from according to the texture of the burr, the speed at which it must be run 
and the number of the furrows, particularly the number to the quarter. As 
regards the question of close or open stone influencing the draft, we may 



334 VARIOUS MILLSTONE DRESSES. 

say that if the stone is close there may be in some stones say 5 inches 
draft, and if open 5^. 

As a general rule the Germans say that without aspiration the draft 
should be three-fortieths of the stone diameter, and with aspiration one-six- 
teenth. In certain cases the short furrows may be allowed to run into the 
leaders before them. With close-grained stones this may be recommended 
for those who are not very skillful in handling them, although with correct 
dressing this necessity will not be felt. 

The angle of intersection of straight furrows increases in proportion as 
this direction diverges from the centre of the stone, and vice versa, the angle 
must be small in projJortion as the divergence is less. 

In Fig. 229 we show a stone on which are drawn six different lines indi- 
cating the direction of the furrows : a b i?, the diameter of the stone, and 
c ^ the diameter of the dotted eye. The circle ^ /divides the radius of the 
stone into two different parts, and enables us to compare in the case of all 
six of the different kinds of leaders the angles of intersection formed by the 
leaders on the runner and those on the bed. 

It is easy to see that furrows II and 11' intersect at angles entirely differ- 
ent from that formed by I and I', and these again form a different angle 



Fig. 229. 

from IIP and III', etc. The angle of intersection of II and II' is greater 
than that of I and I', and so on, the angle of intersection increasing with 
the increased size of the draft circle. 

The question of draft runs very closely into that of furrow outline. In 
all quarter dresses having parallel secondary furrows, whether the leaders are 
straight, circular, or spiral," the draft of the short furrows is greater than that 
of the leaders ; and if it be a disadvantage to have greater crossing angle at 
the skirt than at the eye, the furrows that have the most draft will have 
the greatest crossing angle. If the short furrows are given the same draft as 
the leaders, they will have the same crossing angle at a given distance from 
the skirt, as the leaders have. There may be two or three different lengths 
of diverging furrows, all having the same draft at the skirt, though some of 
them may not reach more than half way in toward the eye. Dresses of this 
type will not be strictly " quarter dresses," although the leaders apparently 
divide them into so-called "quarters," or fields. 

Ganzl & Wolff say that many millers suppose that the proper draft for 
the furrows is of real importance, while others think that of so little import- 
ance that they think that if the stone is open or porous there need not be any 



DEPTH OF FURROW. 335 

furrows at all. There is upon record a test with a 5-foot stone running one 
hundred to one hundred and five turns, having a draft of four inches and 
sixteen quarters with three furrows to the quarter. This stone being run was 
then dressed down to the depth of the furrows and a new dress put in, with 
three inches draft, twelve quarters each having two furrows. Then, noting 
the product, the stone was redressed and given only ten leaders, with three 
inches draught. The second dress showed no difference in quantity of chop, 
and the difference in the last case was so little that it might be ascribed as 
well to faulty observation as to faulty distribution by the furrows. 

Depth of Furrow. — Here again comes conflict. " The furrow should 
be shallow, because the runner should commence to work upon the grain of 
wheat the moment it starts up the incline of the furrow. If the furrow be 
deeper than the thickness of a grain of wheat, the grain will have traveled 
part of the way up before it commences to be acted upon by the runner. 
(This is supposing the case of an upper-runner, and the principle is the 
same for an under-runner.) 

" If there is any difference between the furrows in the upper and lower 
stone, those in the upper should be the deeper. Those in the lower should 
not be deep enough to let a grain of wheat be covered. 

" Middlings do not need deep furrows, but they should be deep enough to 
let the stones take the feed. Sometimes, with a high rate of speed, the driver 
and bail will prevent the middlings from feeding." 

The author considers the rule that " the furrow depth should not be as 
great as the thickness of a grain of wheat," not based on any sound 
principle. Carried out to the next stage, and in the same proportion, 
furrows for middlings reduction would be of almost inappreciable depth. 
Less depth is needed where there is a "millstone exhaust." 

" When furrows are not deep enough they will grind too slowly, are too 
apt to heat the flour, and the bran will not come out so clean ; when too 
deep they will throw out small parts unground." 

*' Furrows, if they are given much draft, will not bear to be deep. Too 
much draft makes much coarse meal. Some advise making the furrows in 
the bed only half the depth of those in the runner, alleging that deep furrows 
in the bed are apt to throw out grain without proper grinding." 

The Furrow Section. — "The section of the furrows depends very 
much upon whether you are grinding high or low, and require many or few 
middlings. For low grinding, a perfectly true taper is recommended from the 
first or back edge up to the feather, the depth being | inch on the back up 
to ^ or less on the feather for a new stone. When the stones are in good 
face the feather should not be deeper than the depth of a good heavy crack." 
Many think that the feather-edge should have no shoulder at all, and we 
are inclined to agree with them. 

" Perhaps the reason that hollow or " gouge " furrows — that if, those with 
concave surface, have in some cases been found to grind cooler than flat 
furrows, is that they give more discharge, which was very likely needed for 
an excessive feed. In such a case it would be better to widen than to gouge 
the furrows." 



336 



VARIOUS MILLSTONE DRESSES. 



The writer considers that the cutting work done by the back edge of the 
furrow is rather limited, and that the best section is that of a right-angled 
triange, having the right angle B in the bottom, the obtuse angle A at 
the front, and the acute angle C at the "feather-edge," or back, thus: 




Fig. 230.— Proper Furrow Section. 



This gives freer action than where the obtuse angle A is at the bottom 
and the front edge AB is vertical, thus : 




Fig. 231. — Wrong Furrow Section. 

and the first section is easier made with a pick or an emery wheel. 

"Smoothness of Lands and Furrows. — Smooth burr faces do 
better on hard wheat than on soft." 

" There is no use in making the furrows like a bastard file, unless the 
object be to make flour that will bolt specky through a No. 16 cloth." 





Fig. 232.— Straight Quarter Dress. Fig. 233.— Sickle Quarter Dress. 

" The more even the porosity of the stones the more regular the furrows 
will be, and the more regular the ground product." 

The smooth and the rough furrow advocates do battle on this head, 
without ev^r coming to much of a conclusion, or, rather, change of opinions. 
It seems, however, as though the smooth furrows cut the bran up less than 
rough ones, in wheat reduction ; and many millers, while religiously adhering 
to "cracking" on the face, rub the furrows smooth with a corundum block. 

Cracking the faces is now done finer and finer each year ; the " diamond 



QUARTER DRESS— COMPROMISE DRESS, ETC. 



337 



dressers " having paved the way for this, and the emery and corundum 
wheel dressers following them up toward absolutely smooth land and furrow. 

QiUarter Dress. — In the cut, Fig. 232 is the old straight quarter dress, 
still much used in the South and in Great Britain. Fig. 233, a modification 
of the quarter dress, is the sickle. 

Compromise Dress. — The " compromise " dress proceeds in a straight 
line across from the eye to within six inches of the skirt, and then turns a 
corner like the short furrows of the quarter-dress. We name this dress as an 
instance of " how not to do it." It combines the disadvantages of the sickle 
dress and those of the quarter, lacking the even regular draft of the sickle 
and the freedom of furrows of the quarter. 

Pennsylvania and Ne^v Jersey Dress. — In Pennsylvania and 
New Jersey there is a very common dress, which maybe adapted to any kind 
of dress without cutting away the old furrows. In all cases the upper stone, 
whether used as the runner or not, is cut in furrows with a deep square 
channel at the back, and feathered at the front ; while the lower stone, 
whether used as the runner or not, is cut in shallow furrows of equal gauge 





Fig. 234.— Dickso.-j Dress (Runner). 



Fig. 235. — Dickson Dress (Bed). 



throughout. The furrows are broad and the lands are narrow. A 4-foot 
stone, with twelve leading furrows, will be \\ inches wide at the eye and 2\ 
at the skirt, \ inch deep at the back, ^ inch at the shoulder. 

Old Style Equalizing Dress. — In nearly all cases the equalizing 
dress has 19 leaders and 19 short ones, the furrows being i;^ inches wide, and 
\ inch deep at the eye of the stone, and y^ at the skirt, with one inch draft 
to the foot for the leaders, and \\ to the foot for the short ones. With this 
dress the speed is about 200 revolutions. 

NeTV Style Equalizing Dress. — This has 20 to 21 leading furrows, 
if to i-^ inches wide, draft according to the speed. 

Combination Dress. — A "combination" dress used in our Western 
States has 14 sections, each of 3 furrows — the leader with 'l\ inch draft to 
the foot ; second furrow connected with it at the eye ; furrow depth, \ inch 
at the eye, -^ at the skirt ; feather-edge, except for 8 inches at the eye, where 
there is nearly -^ inch cutting edge. At the eye the furrows cross each other 



338 



VARIOUS MILLSTONE DRESSES. 



about at right angles ; and half way to the skirt about 40°. The separation 
of bran and flour should take place at the skirt. 

Dickson Dress. — The Dickson dress is shown in Figs. 234 and 235, 
the first being the runner and the second the bed. The cuts represent 4-foot 
stones with the grinding surfaces reduced to three feet. There should be 
about 20 furrows, a, in the stone, with about three inches draft from the 
centre of the eye. The second course of furrows, b^ has double the number 




Fig. 236. — Jones Dress. 

of a, with at least five inches draft. More draft is given in the second course 
than in the first, because the grinding mass is more liable to clog when well 
pulverized than when only partially ground. The outside furrows, ^, are 
not intended to grind, but merely to act as conveyors to deliver the ground 
mass. The bed-stone B, from course b, is dressed down below the grinding 
surfaces about \ inch. 




lilii 


IIINIlllllll 1 




!iiiiii 


IIIII1IIII 


^^^ "--'-lia^iiHniiii'jlinilllji;^ 


|li'ltllinill;imTlTr77ni.,, _^ihiilllliliili,1l:l';ii:iil'iumiinj 


tiiiiiiiiiniuiiiiiiiiiiiiii 





Fig. 237. 

The Jones Dress. — The Jones dress, out of which so much money was 
made in England, is shown in Fig. 236. The stone has a central inclined 
concentric circumferential depression, d, around the eye E, and comprises 
one-fourth of the surface of the stone; a, a\ a'' are the grinding surfaces or 
lands, and b the furrows, and some of the lands terminate in an acute angle 
at the eye of the stone ; this, as well as the intermediate lands a\ a^, 



JONES— BO WMAN—ARND T. 



339 



diminish in width from the curb inward, so as to allow the offal to be 
completely cleaned. This dress is claimed to enlarge the ingress of air and 
decrease the grinding surface, thus making a large quantity of cool middlings. 
The chief fault of this dress is that the intersection angle is very large 
at the eye, and decreases rapidly toward the skirt, giving a favorable angle 
for entrance, but an unfavorable angle for discharge. This fault, on the 
other hand, is overcome by the parallel dressing. 




Fig. 238. — Bowman Dress. 

The dress shown in Fig. 237, is recommended by one of the corre- 
spondents of the Millers' Journal. The two quarters opposite A are for 
a 4-foot, close, new stock burr, with 12 quarters and 3 furrows to the 
quarter, with 3 inches draft from the feather-edge of the stone. In very 
open or old quarry stone, the same writer recognized two furrows to the 
quarter, like that opposite B. For three feet and under, the dress similar to 




Fig. 239.— Arndt Dress — Lower Stone of Under-Runner for Rye. 

that at C is preferred by the same writer, with the short furrows in front of 
the leading ones to enter them at the eye. 

Bo'WinarL Dress. — The Bowman dress, shown in Fig. 238, is claimed 
to run very cool, and that it can be adapted to any style of dress without 
having to cut the stone away. In this dress the furrows in the lower stones 
are not so deep as those in the longer, and are made broad with narrow lands. 



340 VARIOUS MILLSTONE DRESSES. 

Arndt'S Dress. — In Arndt's dress the upper-runner has not exactly 
the same dress as the upper. In Fig. 239 is shown the Arndt dress for a 
lower or runner for rye, and in Fig. 240 that for wheat. Fig. 241 shows the 
upper or stationary stone for either wheat or rye. The furrows for the 
lower stone or runner have less draft than those of the upper or stationary 
stone. By changing the number of quarters this inclination may be varied; 




Fig. 240. — Arndt Dress — Lower Stone of Under-Runner for Wheat. 

the angle of the short furrows with the radius being less, with smaller fur- 
rows than with large. Arndt, for a stone with 88 to 92 turns, and for two 
breaks, gives 14 quarters to the bed-stone ; gives for the third five breaks, 
no to 115 turns and 12 quarters ; for the six inch to eight inch break, 115 
to 120 turns and 10 quarters. It does not follow that there should be 
only 8 quarters and 90 to 100 turns for the ninth to the eleventh break. 




Fig. 241. — Arndt Dress — Upper Stone of Under-Runner. 

because this would give six short furrows, and the shortest one would 
have far too much draft. In Arndt's dress the slope of the leaders is the 
same as in all ordinary dress, but the slope of the short furrows is reversed ; 
that is, "the feather-edge upon the wrong side," according to the miller's 
usual custom. The short parallel furrows are narrower than the leaders. 
The harder the stone, the more parallel furrows there may be. 



IVARD'S MILLSTONE FORMULA. 



341 



Ward's Millstone Formula. — By this method all the joints run in 
the back edges of the main furrows, thus preventing them from crossing the 
grinding surface of the lands. (See Figs. 242 and 243.) 

One objection to the circle or sickle dress is that, having so many furrows 
crowded into the eye, these inner ends must be the smallest, thus affording 
much less space for the grain to pass through. Another objection is that 
the varying curve prevents the use of painted furrow patterns to keep the 
furrows of even size and shape and perfect finish. The furrows should be 
dressed up frequently, just as a saw should be frequently set as well as filed. 
One frequently urged objection to the circle dress is the apparent difficulty 
of laying out a curve ; but this is really an easy matter. 

There may be said, in addition, against the circle dress, that it requires more 
time to keep the stone in proper order than the straight. 

Hughes made experiments with the circular and the old-fashioned straight 
quarter-dress, with the result that the meal issuing from the stone was found 
to be warmer by ten to tvventy degrees Fahrenheit in the circular dress stone. 





Fig. 242.— Common Quarter Dress— Furrows 
Crossing Joints. 



Fig. 243. — Ward's Dress— Furrows Along 
Joints. 



Dressing for Re-grinding. — On a 30-inch stone, the under stone 
being a runner, should have a bosom of \ inch, running out and becoming 
shallower six inches from the outer guy. Middlings do not require deep fur- 
rows ; they need a tolerably close burr. The feather-edge need not be prom- 
inent ; the burrs must be in perfect face, but not too sharp. The feed should 
be light. 

The great problem under the new process is how to make the most mid- 
dlings out of wheat. The Committee on Mill Machinery at the Millers' Con- 
vention at Cincinnati stated that it had heard of fifty per cent, of middlings 
claimed from one hundred furrows in a 4-foot stone, and the same result 
claimed with the three-quarter dress. 

To make as much middlings as possible, the stones must be well dressed, 
perfectly balanced and the face perfectly true. There may be fourteen lead- 
ing furrows, each with two short ones, forty-two in all, varying in width from 
one and three-quarters to two, or even two and a quarter, inches at the skirt. 



342 VARIOUS MILLSTONE DRESSES. 

Supposing we are using the same quality of burr in each case, we will 
note that old process milling requires wide lands and narrow furrows, whereas 
the new demands narrow lands and wide furrows, and also the face must be 
truer and smoother. For high grinding, about sixty-five per cent, of the 
entire surface should be in furrow. At least one-third of the diameter of the 
stone should be allowed for bosom. Perhaps it would be better yet if a per- 
fectly graduated bosom was made from the eye to within two inches of the 
verge, making the depth from three to four thicknesses of paper down to 
nothing. 

"Burrs 48 inches in diameter, running at 180 revolutions, and of medium 
old or open new stock, may be dressed about as follows : 14 sections each 
with three furrows i-^ inches wide, \ inch deep at the eye, and a little shal- 
lower at the skirt. The furrows may be slightly concave. The leading fur- 
rows may have four inches drop to the feather-edge, and the other two 
five and a half inches." 

Otlier Dresses. — For old process, a dress recommended by a Connecti- 
cut miller has 14 quarters, each with 3 furrows, 4 inches draft to the deep 
side or draft line, furrows if inches wide from eye to skirt, depth \ inch 
at the eye, f inch at the skirt. 

"For new process wheat grinding, a 42-inch stone may have 16-inch eye; 
24 quarters, 2 furrows to quarter, furrows i inch wide, -^^ inch deep at skirt, 
\ inch at eye. In old process wheat grinding, a 42-inch stone may have 17 
quarters, 2 furrows to the quarter, i^ inches wide at skirt, if inches at eye, 
■|- inch deep at skirt, y^ inch deep at eye. A 42-inch corn stone should 
have open hard blocks, i inch to foot draft, 17 quarters, 2 furrows to quarter, 
i-| inches wide straight through, ^ inch deep at skirt, f inch at eye. For 
middlings (old process), a 36-inch stone may have the same dress as for old 
process wheat grinding. The stones should be hard and comparatively close. 
Middlings may have a 30-inch stone, with 22 furrows, straight into the 
eye, and the same width and depth as for a wheat stone. Rye requires a 
middle dress between corn and wheat. Nearly every miller has his own views 
as to the proper dress for new process grinding." (Straub Mill Co.) 

"Old process milling demanded three-quarters of the stone face to be 
lands and one-quarter furrows ; new process requires the reverse, /'. e., one- 
quarter lands to three-quarters furrows. To reduce the lands surface, either 
widen the furrows or cut narrow ones (say ^ inch wide) parallel with the 
main, starting at the skirt and running into the main." 

For grinding middlings, the furrows should be kept about the same as for 
wheat, it being seldom necessary to crack the face. For corn, the burrs can 
hardly be kept too sharp. 

" In flouring soft grades of wheat in California and in the South, a quick 
motion and line-cracked surface would do good work, where they would be 
ruinous for hard Northern wheat." 

" The hard wheat of Northern Europe looks like birds' nails. It is ex- 
ceedingly hard, and should be ground on a stone with shallow furrows." 

"For grinding both hard and soft wheat, Pallett recommends thirteen or 
fourteen equal quarters, with three-fourths to each furrow, to be one and 



OPINIONS ABOUT DRESS. 343 

three-eighth inches wide, having the second furrows cut into the leading one, 
but leaving the width of the stone constant at the inner end of the short fur- 
row, giving the leader five inches draft, and making them a shade deeper at the 
eye." 

" For corn grinding the furrows are better a little rounding, with double 
the depth of the feather-edge required for wheat." 

One way to prevent heating is to dress without a bosom, then divide a 
4-foot burr into sixteen divisions with straight furrows, draught one-half 
the diameter of the rock. Lay off the lands and furrows \ inch each, dress- 
ing smooth. Sink the furrow at the eye \ inch for corn, running out to y^j- ; 
for wheat y\ at the eye running to -g- at the skirt. If you crack, crack the 
lands in straight lines, square with the draft of cross lines, so as to make 
lines lace in the runner and bed direct. 

To prevent or lessen heating, give more bosom, or else make the furrows 
deeper and wider, making the leading furrows at the eye nearly \ inch deep, 
tapering gradually to the surface. 

For middlings, Littkjohn thinks that the furrows should have a feather- 
edge and smooth surface, and the proportions of land and furrow about 
equal. 

A Canadian miller recommends for a 3-|-foot stone, old process, 12 sec- 
tions, 12 long and 24 short furrows; furrows \\ inches wide and of equal 
width throughout ; short furrows not cut through to the long ones, but half 
an inch left between the end of the short and the side of the long one ; 
depth, -finch at the back, smooth dressed up to a feather-edge : draft, 4:^ 
inches from the feather-edge ; speed, 190 ; 18 to 20 cracks per inch for seven 
inches from the skirt. From the edge of the cracked portion to the eye, as 
smooth as possible with little bosom. 



^W^ 



CHAPTER XXV. 

DRESSING THE BURRS. 

First Dress— Picks — Tempering Mill Picks and Chisels— Position in Dressing— Paint Staff— Proof Staff 
— Staffing— Direction of Furrows — Draft Square — Furrow Strip — Redressing and Cracking- 
Cleaning Millstones— Mending Burr Faces— Pick Burr Dresser— Diamond Dressing — Benton 
Dresser — Hand Tools. 

Tlie First Dress — "Well begun is half done." Burr dressing may 
be divided into two portions, the original dressing, and the cracking and 
other treatment which keep them in good condition. It is not so easy 
for the manufacturer of the stone to dress it so as to get the best work 
out under the varying conditions prevailing among his customers, as for 
the customer, knowing his speed, material, and product and a hundred 
other elements which enter into this: — supposing, of course, that the miller has 
a sufficiently thorough knowledge of his art to enable him to choose and 
apply the best method for his particular case. 

Let us commence by examining what is to be done in order to fit the 
stone for grinding. In buying burrs we may receive them dressed or un- 
dressed, that is, if we understand by dressing simply the rough pick-work 
which passes for such at many factories. The stone maker rarely does more 
than to divide the stone into a number of fields which he supplies with fur- 
rows. Makers are generally content when the grinding surfaces of the stones 
are perfectly even, although in many cases these factory-staffed faces neither 
allow the miller to redress them, or are themselves ready for grinding. Very 
often the factory dressing has to be ground off with sand or glass, or by let- 
ting the stones grind together. The first thing that the miller has to do to 
rectify the new stone is to begin with the faces before the stone is put in 
place to work. For this purpose he needs a superior staff, kept in perfect 
order, and a good supply of the best picks, sharp, well tempered, and of 
weight and size adapted for the work to be done. Picks can never be too 
sharp nor too carefully handled, otherwise cavities or depressions will be 
reproduced and the grinding faces never brought to a perfect level. 

After the stone has been staffed and picked over ten to twelve times or 
more, and the factory face dressed over, it maybe temporarily put into opera- 
tion, preferably on rye. After two days' use in this capacity, it may be lifted 
once more. Then there is plenty of time for cracking, if cracking is re- 
sorted to, which is not recommended. 

The quality of a dress depends upon the material of the stone, upon the 
condition and excellence of the staff and picks, as well as upon the degree of 
skill and practice and the perseverance of the dresser. When the stone has 
been put in good shape for grinding, it is determined whether the original 



PICKS. 



345 



furrows are the right kind and direction, and whether they are to be allowed 
to remain so or be altered or dressed out. 

Picks. — Picks should be from eight to twelve inches long, with a heft in 
the centre as much as can be kept and the ends slightly concaved, to give a 
good length and even diameter. They are made of i:^-inch square bar. If 
no eyes are ordered, if-inch square is used for 3-pound to 3|^-pound furrow^ 
ing picks. For heavier picks, without eyes, i^-inch square is used. The 
aim should be to keep the picks as short as possible, so that they will strike 
solid and not spring. 

The ordinary picks will weigh about as follows : 



Width of Blade. 


Cracking. 


Furrowing. 


l^ inches. 

^Yz " 
2 


2 lbs. 
2J^, 3. yA 
2^ 


zVz lbs. 
3, 3X. 4 



Most pick makers advise the use of the grindstone only, for sharpening, 
and call particular attention to the desirability of using a quantity of water 
and low pressure. Many a good pick is spoiled by grinding on a dry stone 
and bearing on hard, by which means a pick can be spoiled very quickly. 
The miller is apt to say the pick is too soft and to send it back to be re- 
tempered. A pick can be spoiled so that it will not cut, by heavy rubbing 
on the stone that millers have on the husk when dressing. Packages and 
boxes containing picks sent to be repaired should not only be plainly marked 
with the address of the pick maker, but also have upon them the names of 
the parties to whom they are to be returned. 

English steel is the most reliable for all kinds of picks. The furrow pick 
should not exceed ten inches in length by one and one-half inches in width, 
and the weight from three to four pounds. Cracking picks should be from 
eleven to twelve inches long and not more than two inches wide. The 
brighter the blue the better the temper, if the grain is close. The best mode 
of tempering is by careful heating in charcoal. The best solution, other 
things being considered, is the one that will give the hardness and toughness 
required at the lowest temperature. 

A very fine preparation for making steel very hard is composed of wheat 
flour, salt and water, using, say, two teaspoonfuls of water, one-half teaspoon- 
ful of flour, and one of salt. Heat the steel to be hardened enough to coat 
it with the paste by immersing it in the composition, after which heat it to a 
cherry red and plunge it in cold soft water. If properly done, the steel will 
come out with a beautiful white surface. It is said that Stubbs' files are 
hardened in this way. 

Picks may be divided into those wilh eyes, those without eyes, knife picks 
and patent picks. Those without eyes are far better than those with eyes, 
being more firmly held. For those without eyes there should be two handles, 
one short for furrowing, one long for lands. They are better too heavy than 
too light. Thin picks are disliked by reason of their tendency to tremble. 
Patent or compound picks have the body of wrought iron, with a little steel 



346 



DRESSING THE BURRS. 



plate cat each end. They save pick handles, but are liable to tremble like the 
blades. 

A well known maker of mill picks, in expressing his opinion as to the 
requisites of good picks, says : " In the raanufactureof Ai mill picks, nothing 
but a close-grained cast steel should be used. This quality of the metal is 
told by the superior brightness and closeness of the steel when broken. The 
best shape for a furrowing pick is short, with the weight in the centre to 
avoid spring. The weight should be three and a quarter to four pounds. 
Cracking picks of the best shape should not exceed eleven inches long, with 
a natural bevel from the centre, so as to hold the handle better. To test the 
quality of a mill pick, it must be broken. A blue color shows hardness and 
temper. Grit, i. e., cutting quality, is determined by a lighter blue and close- 
ness of grain. Crystals denote 'burned ' or overheated steel. Blacksmiths 
cannot temper picks, because as each piece of steel differs in the quantity 
of carbon it contains, it is only by experience that it can be determined to 
what degree of heat each piece must be subjected and when the tempering 
must be done. Three picks, using both ends with one grinding, should dress 
a 4-foot bed-stone. Many makers claim that a pick dressed by other parties 




Fig. 244. — Eyeless Pick. 




Fig. 245. — Pick with Eye. 

and burned is ruined. This is not so. Unless the cracks are visible to the 
eye, any burned pick can be restored to its original cutting quality by a skill- 
ful steel worker. To prove this, the best picks are made from old ones which 
have been heated many times. Not more than one condemned pick in a 
hundred but what can be restored." Fig. 244 shows the pick for use in a 
patent head ; Fig 245 is supplied with an eye. 

The picks made by John C. Higgins, 163 West Kinzie Street, Chicago, 
may be recommended. 

Tempering Mill Picks and Chisels. — i. Heat the pick to a blood- 
red heat, and then hammer it till nearly cold ; again heat it to a blood-red 
and quench as quickly as possible in 3 gallons of water, in which are dissolved 
2 ounces of oil of vitriol, 2 ounces of soda, and \ ounce of saltpetre ; or, 
2 ounces of sal-ammoniac, 2 ounces of spirits of nitre, i ounce oil of vitriol — 
the pick to remain in the liquid until it is cold. 2. One ounce of white arsenic, 
1 ounce of spirits of salts, i ounce of sal-ammoniac, dissolved in 4 gallons 
of spring-water, and kept in a tube or iron phial for use. Heat the pick to 
a blood-red heat ; then quench it in this mixture ; draw it gently over the 
clean fire till the spittle flashes off it ; then let it cool. 3. To 3 gallons of 
water add 3 ounces spirits of nitre, 3 ounces s])irits of hartshorn, 3 ounces 



POSITION IN DRESSING. 



347 



of white vitriol, 3 ounces of sal-ammoniac, 3 ounces of alum, 6 ounces of 
salt, with a double handful of hoof parings ; the steel should be heated a 
dark cherry red. Used to temper picks for cutting French burr-stones. 

Another formula is as follows : i. Take 2 gallons rain-water, i ounce of 
corrosive sublimate, i of sal-ammoniac, i of saltpetre, i-j- pints of rock salt. 
The picks should be heated to a cherry red and cooled in the bath. The 
salt gives hardness, and the other ingredients toughness to the steel ; and 
they will not break if they are left without drawing the temper. 2. After 
working the steel carefully, prepare a bath of lead heated to the boiling 
point, which will be indicated by a slight agitation of the surface. In it 




Fig. 246.— Pick :n Patent Handle. 



place the end of the pick to the depth of one and one-half inches until 
heated to the temperature of the lead, then plunge immediately in clear cold 
water. The temper will be just right if the bath is at the temperature re- 
quired. The principal requisites in making mill picks are : First, get good 
steel. Second, \york it at a low heat ; most blacksmiths injure steel by over- 
heating. Third, heat for tempering without direct exposure to the fire. The 
lead bath acts merely as a protection against the heat, which is almost always 
too great to temper well. 

Position in Dressing. — Take a suitable cushion ; place it upon the 
stone ; lie down upon it, resting upon the left hip and elbow ; take the pick 
firmly in the right hand near the end of the handle ; clasp the handle loosely 
with the left hand near the pick, and, proceeding to work, dressing from you, 
crack the land the width of the pick. Do the work with the right hand, 
using the left to steady and guide the pick. Many millers have a flexible 
leather strap under the pick handle, as a guard to prevent the back of the 
hand from getting full of steel and stone from the picking. 

23 



348 



DRESSING THE BURRS. 



Staffing. — Two surfaces working against each other tend to become 
parts of spheres. Either of them may become concave and the other convex 
with various degrees of curvature. 

A plane surface, the line of separation between concavity and convexity, 
is the most difficult to hit — just as it is a great deal more difficult to make 
a perfect straight line than a perfect circle. 





Fig. 247. 



Fig. 247A. 



Fig. 247 shows three beds, and Fig. 247A the same supplemented by three 
others. Not only must each bed be made true from end to end before be- 
ginning' the next, but each must staff perfectly true on all beds that it 
crosses. To effect this a true paint staff must be used. 

Fig. 248 shows the iron paint-staff, with level ; Fig. 249 a wooden proof- 
staff, and Fig. 250 its case. 







Fig. 248. — Iron Paint-Staff. 

The Paint-Staff. — The paint-staff is to the miller what the surface 
plate is to the machinist. It is better bought than home-made. When of 
wood it should be composed of four or more strips of well-seasoned material — 
cherry is the best — trued up and glued together, with the fibres so lying as 
to prevent warping. 

They can be made absolutely true only by making three at a time, testing 
the first with the second, and the second with the third, turning end for end. 




Fig. 24 



-Wooden Red-Staff. 



They are proved from time to time by applying them to the proof-staff, 
which is made of cast iron, planed, filed, scraped, and which, to insure abso- 
lute accuracy, should be made and tested three at a time, in the same manner 
as the proof-staff. The ordinary planing machines, whether wood or iron, 
will not plane out of wind. The proof and paint staffs should be tested 
together by applying them and looking under them. Seeing no light places 



STAFFING. 



349 



under any portion of the edges, they should be turned end for end and 
tested in the same manner. 

They should be further tested by laying four pieces of tissue-paper on 
the proof-staff and laying the paint-staff on them ; they should be painted 
equally at all points along the staffs. Unless, a red-staff has its pores well 
filled it will be apt to deflect when paint is applied. The triangular staff 
made out of nine well-seasoned boards (that is, three on each wing) will 
keep in order longer than the ordinary straight staff. It should be remem- 




FiG. 250. — Case for Proof-Staff. 

bered that, if the red-staff is out of true, the error will be doubled when 
the two stones, which are trued with it, are placed face together. The proof- 
staff should never be removed from its case, much less used as a level. "As 
the different blocks of a stone expand differently by the heat, the burr should 
be staffed when warm." 

In how many mills do we find the most accurate appliances provided, and 
either carelessly or ignorantly used, or else positively abused, so as to have 
their value lessened. The paint-staff should never be used for any purpose 




Fig. 251. 



Circular Iron Proof-Staff. 



Fig. 252. 



except staffing, and when used for staffing it should be used intelligently and 
with care, so that it can be depended upon. 

In staffing, keep the staff away from the edge of the stone, as this is apt 
to be worn or broken away by bad balancing or other causes. 

Figs. 251 and 252 show the circular iron proof-staff, which is self- 
explanatory. 

The circular staff indicates at once a high place, but cannot mark a low 
place, as it takes a bearing only on that part that wants dressing. It needs 



350 DRESSING THE BURRS. 

less skillful handling than a straight staff does. Perhaps better work than 
with either can be done with a triangular iron staff, which combines all the 
advantages of the straight staff and the circular, and it is as easily handled 
as the wooden staff, while doing as perfect work as the cumbrous circular 
staff. 




Fig. 253. 

The first thing to be done in dressing a millstone is to make its face 
plane and ready for the furrows. To do this, lay the stone on its back, level 
its face as nearly true as possible ; then, with the paint staff (which we 
describe at length under another head), mark the high spots, pick these off 
and rub the face of the stone with a sharp burr-block or a regular dresser. 




Fig. 254. 

To take it "out of wind," fit into the eye a piece of board, into which 
drive a screw or a nail as a centre, and strike a circle on the face of the stone 
two inches from the verge.* Divide this in o three equal parts by stepping 
off the radius on the circumference (which divides it into six parts), and 

* To get the exact centre, divide the skirt into four quarters, by stepping, and draw two intersecting 
diameters through these from equidistant points. Or, talce from equidistant points. A, A', B B (Figs, 
253, 254) ; draw arcs, either lapping or nearing one another, and in the loops or squares formed by 
these arcs, draw diagonals. Intersecting at C. (This is where there is no straight edge long enough to 
cross the stone, and no cord handy.) 



STAFFING. 351 

taking every other point of division. Laying the staff on the inside of two 
of these points, draw a line clear across terminating at both ends in the verge, 
and in a similar way mark off three other lines on the face of the stone. 
Draw parallel lines about an inch farther from the first lines than the width 
of your staff. The strips between these parallel lines are called beds. 

Painting the staff lightly, lay its face on one of the beds, and move it 
gently lengthwise. Pick off the higher points lightly and rub with a burr- 
block. Continue staffing and picking until the staff paints the whole length 
and the bed is nearly smooth ; then work the other beds the same way, taking 
nothing off the i)oint where they intersect one another. With the stone true 
in these three different directions, it is comparatively easy to make its whole 
surface true. When the face is true with the beds, wipe the staff and lay it 
on the face. If light can be seen between the staff and the stone, the face is 




Fig. 255. 

untrue. It must be staffed and worked until the stone points evenly all over 
and the staff does not rock. Of course small stones are easier taken out of 
wind than larger ones, because the same amount of surface has not to be 
picked off. 

Divide the stone into the required number of quarters.* Make a point at 
each quarter ; then, with a perfectly true furrow stick, the width the furrows 
are to be, lay off the leading furrows by laying it on the outside of the draft 
circle, having one end on the circle, the other end and same edge of the 
stick on the quarter points, marking them with a quill. If the stone is to be 
run "with the sun," the furrow stick must be laid upon the right-hand side 
of the draft circle and quarter points ; if to run "against the sun," lay it the 
reverse. After the leaders are laid off, step them with the compass and correct 
them ; then, taking the landstick, which is the width the lands are to be, 
determined by the number of short furrows between the leaders, continue 
around until all the furrows are laid off. Of course they must be of equal 
width, one with another. 

For cutting, mark lightly with a light sharp pick the outline of the fur- 
rows, marking the feather-edge (that which is next the draft circle) only 

*See Fig. 255. 



352 



DRESSING THE BURRS. 



lightly. Then with a heavy pick rough out the middle to nearly the desired 
depth, keeping the back nearly straight from the face of the stone, and nearly 
a quarter of an inch deep, tapering up the feather-edge. Then take a sharp 
pick and make them even and smooth their whole length. The bed-stone 
and the runner generally receive the same dress. 

Direction of Furrows. — "The side of the draft circle on which the 
pattern is to be applied depends upon the way the stone runs. 

" As a rule it may be stated that if the stone runs from right to left or 
against the sun, as indicated by the cut, then the leaders must be tangent 
with the draft circle on the left or toward the dresser. 

" If it revolves from left to right or sunwise, as shown, then all of the 
leaders must form tangent toward the dresser from the draft circle. 

"The furrows must always lie in front of the spindle. If the stone turns 
from right to left, then all the furrows must lie to the left in front of the 




Fig. 256.— Using the Draft Square. 

spindle ; if the stone turns with the sun, then they must lie to the right in 
front of the spindle." 

Draft Square. — The draft square may be applied, as shown, to the 
pin in the draft-board and measurements at the outer circle on the edge of 
the stone. Care must be taken to get the draft equal on all the furrows. 

Furrow Strip. — To make all furrows precisely the same depth, cut a 
wooden strip four or five inches long and the proper section of the furrows. 
By this paint may be applied to the furrows to work them even. For flouring 
make the furrows as smooth as the face. Rough furrows make specky flour. 
Many a fault charged to the bolt belongs to the burr. 

Redressing and Cracking. — At least every two or three months the 
furrow should be re-dressed. Every time the stone is taken up would be 
much better. In a busy mill the best stone requires to be cracked every three 
or four days. Cracking, however, is not now used for granulating. Cracking 
is cutting the face in parallel lines with the furrows, and when well done in- 
creases the capacity of the burrs and the quality of the flour. Where stones 



DIRECTION OF FURRO WS, ETC. 353 

have twenty-six or thirty cracks per square inch they do not require so much 
pressure. After taking up, the face should be rubbed all over with a piece 
of soft sandstone, then swept and staffed. If the stone is highest at the eye and 
breast*, clean off this face till the staff paints equally all over, then crack the 
rest of the surface. Should it be in good face when taken up, crack it all 
over with a sharp pick without breaking the face, then tallow the spindle 
neck. If the spindle is loose, tighten it, tram it, then put the stone down 
again." 

" By cracking, not only part of the grinding surface is cut away, and the 
grain is too much chopped up. The stone is sharper after being cracked 
than before and will grind faster, but the flour will not be so good, being 
dark by reason of the particles of bran being cut up. When the burr begins 
to get smooth it begins to make better flour." 

" Formerly thirty or forty cracks per inch were put in millstones to 
reduce and sharpen the grinding surface. Now this custom is superseded by' 
the use of two-thirds furrow surface." 

" With hard blocks the cracks should be deeper and closer than in 
softer ones." 

" When the stones throw out small round pieces with parts of the meal 
ground too close this shows that they are out of face, and working entirely 
on some high part. In this case take them up ; if the face prove true, the 
furrows may be too deep and rough, and should be filled with cement to the 
proper depth." 

A better way than to sharpen all the furrows at once is to freshen up four 
or more furrows at equal distances apart on the bed, when the stone is taken 
up to dress ; then next time that the stone is up freshen four furrows on the 
runner, and so on. By this means the action of the stone will be kept more 
even than if all the furrows are brought to life at one time, and all allowed 
to get in bad condition at once. 

Cleaning Millstones. — Vinegar or apple cider is often used for clean- 
ing the face. Some use a piece of soft sandstone. A twig broom does well 
to loosen the caked material, and may be followed by a brush. Some use a 
hand-bellows to clean out the larger furrows. A solution of borax is some- 
times used to open the pores and remove the glaze in stones, and muriatic 
acid and water may be used. Many millers use a piece of leather ten inches 
wide and two feet long, known as a " strap." With this the stones are slapped 
till all the dust is taken out of the pores. 

Many dispense with the washing of the stone ; others wash without know- 
ing why they do it. One good reason for washing is that there are many 
substances, such as garlic, that need to be removed in just this way. 

Another reason is that, when clean, the stones are more readily staffed 
and dressed. Some think that the stone is softened by washing, but this is 
impossible. The stones should be washed every time they are raised. A 
composition for cleaning burr-stones is one gallon hot water, two ounces 
borax, three balls of sal prunella (each the size of a hazel nut) and 
one-quarter pound of washing soda. 

* The breast means the bosom. 



354 - DRESSING THE BURRS. 

" When taking up the stones wet them with warm water, and rub them 
with a scrubbing-brush and a little soap and water, to remove the glaze. 
With a large sponge soak the water off the stone. The burrs which have 
been grinding corn will be apt to have a face saturated with the oil of corn, 
making them greasy. If they have been cracked often for wheat these cracks 
will be closed, and they will not clean the offal." 

Mending Burr Faces. — This should not be postponed. If a fur- 
row crosses a seam, and some of the corners of the seam spall off, the 
cavities should be mended or filled by a cement of four ounce weight of 
No. 4 emery, four ounces of gypsum and four ounces of alum, the alum being 
heated until melted, the plaster being mixed with water to the consistency of 
cream, then all heated together and the emery stirred in well. The cavities 
must be washed with a solution of sal ammoniac before putting in the 



Fig. 257. — Pick Burr Dresser. 

cement. The oxychloride of magnesium, made by adding a solution of chloride 
of magnesium to the oxide of magnesium obtained by calcining magnesite, 
is the best cement for millstones. When used in repairing burr-stones, the 
cavities are wetted with the solution of chloride of magnesium, and the 
powdered oxide, mixed with powdered burr-stone, is rammed in. 

Pick Burr Dresser. — Fig. 257 shows a device intended to make the 
cracks by a pick more uniform in depth and spacing than can be done by 
the hand alone. The arm rests on a swivel block on the carriage J, which 
runs along the bed-plate A, resting on the burr face. A suitable adjustable 
feed motion advances the pick crosswise of the bed-plate at each blow. 

Diamond Dressing. — There are two kinds of diamonds used — " car- 
bons" and " boarts." Carbons are dull and black in color, irregular in shape, 
and have sharp, rough edges. Boarts are brilliants that for their imperfec- 
tions are unfit for polishing. They are generally round and without the 
sharp angles of the carbon, hence not so good for millstone dressing. The best 
carbons come from Brazil ; others from South .Africa and Siberia. Diamond 
dressing is specially adapted for stones to grind middlings, which feed irregu- 
larly and have no bran between the faces of the stones, and hence tend to 
harden their surface and glaze them. S. Dessau, 4 Maiden lane. New York, 



THE BENTON DRESSER. 355 

imports these black diamonds specially for milling and other mechanical pur- 
poses. Caution and experience are necessary in buying carbons, as they vary 
in density and hardness. 

Diamond dressing machines save the time of the miller and of the mill- 
stone. In putting a new diamond point in the machine, care must be taken 
to get its cutting edge parallel with the course of the tool, otherwise it would 
make a broad cut and ruin the diamond. The diamond dressing machine 
will dress four to five pair of burrs a day, thereby saving four to five days ; 
if the mill expenses were twelve dollars a day, the saving would be sixty 
dollars for this time. 

The Benton Dresser.* — The diamond dresser in P. P. Benton's 
patent, No. 222,443, dated December 9, 1879, has a staff-bed, bearing a 
frame, which forms the ways upon which the carriage works. This frame is 
fastened at one end by the bolt permitting it to be inclined to the right for 
furrowing. At the other end of the frame there is a bolt which passes 
through an eccentric in the bed, the working of which raises and allows the 




Fig. 258. 

frame to cut deeper at the eye, and to adjust the cut of the diamond to the 
staffing (Fig. 258). 

In the Uhlinger patent, No. 182,358, July 26, 1876, the upper surface of 
the end cross piece of the base-plate rise to a common central elevation, upon 
the top of which are studs passing through slots in the cross-bars of the bed- 
plate proper, dividing the bed-plate centrally lengthwise. By grooved slotted 
standards and screws the bed-plate is held rigidly at any desired angle. To 
hold it perfectly level, there are wedge pieces which may be turned in. To 
furrow, the wedge pieces are turned out, the desired angle given to the bed- 
plate and the screws tightened. 

In the McFeely patent, 188,022, March 6, 1877, the carriage is upon a 
separate frame having carriage guides. The carriage bed can be tilted to 
any angle corresponding to the furrow, and tightened by thumb-nuts. The 
carriage will travel crosswise up and down the incline of its bed, according 
as it is set. 

In the reissue patent of L. Moore, 7,744, June 19, 1877, there is used in 
connection with the guide-plate a bed-plate, on which the guide-plate is made 
adjustable by means of set screws and packing pieces. 

* Made by the Benton Diamond Burr Dresser Company, La Crosse, Wisconsin. Patented Septem- 
ber 26, 1876 ; March 6, 1877 ; June 19, 1877 ; April 2, 1878 ; April 29, 1879 ; December 9, 1879. The Euro- 
pean agents are William R. Dell & Son, 26 Mark lane, London, E.C., England. The company manufac- 
tures three kinds of machines : "A," " B " and " C." 



356 



DRESSING THE BURRS. 



Emery Wheel Dressers. — These are not in very general use. J. W. 
Hoffman, of Three Rivers, Mich., certifies that an emery-wheel machine 
saves from one-half to two-thirds the labor and time of furrow dressing 
with the pick. The machine should be carefully used in order that it may 
not burn or glaze the millstones. W. R. Cooper, Sag Harbor, N. Y., says 
than an emery wheel dresser has paid its cost in dressing the stones in his 




Fig. 259.— Hand Block Rubber. 

new mill. Walker & Marple, Three Rivers, Mich., says that with an emery 
wheel machine they furrowed four run of 4-foot stones and one run of 
4^-foot stones in seven and a half days. 

Hand Tool. — This is for truing the face and furrows of burrs, cutting 
down high spots, removing glaze, and restoring the stone to its original grit. 






CHAPTER XXVI. 

OPERATION OF THE BURRS. 

Operation of Grinding — Diameter of Burrs — Table of Rim Speeds — Speed of Grinding — Dress and 
Quality of Stone — Trouble in Grinding — Quality of Burr Flour. 

Operation of Grinding. — "The grain falling into the eye is swept 
around between the two irons until caught between the stones. At first it is 
only cracked. As it approaches the skirt it is reduced finer and finer. The 
ratio of increase of velocity cannot be calculated, but the revolving velocity 
of the grain at any point must be somewhere between nothing (that of the 
bed-stone) and the speed of the runner. Its outward progress is modified by 
these two conditions. Its course is complicated and undefinable. If too 
long confined, the flour will be hot and "killed," and will not rise and make 
bread. If it passes through too rapidly it is wastefully ground." 

It is assumed that the material is drawn in between the burrs, partly by 
so-called "centrifugal" action (if in an upper-runner mill), and partly by 
friction. Both these causes tend to carry it out toward the skirt, and are 
aided (very slightly) by the crossing of the furrows, and more by the air 
current, if a "millstone exhaust" is used. With certain conditions of 
furrows there may be some nipping and shearing of the berries ; but 
probably the granulation is based more on the cutting action of the large 
pores of the discs (where these exist) and on a crushing or mashing apart 
between two passing inclined planes. With plenty of furrow surface there 
is probably more cutting or mashing apart. Between smooth lands it is likely 
that tearing apart by friction enters largely into the work ; and with 
roughly cracked lands, grinding is liable to be merely a continued abrasion. 

There is a wide difference of opinion on the above subjects, and an 
almost equally wide variance of practice. A millstone is proverbially a 
difficult thing to see through, and what takes place under it is largely 
a matter for conjecture. 

There was a time when, taking four millers, two of whom had similar, 
and the other two widely dissimilar conditions, the first two would have 
widely different theories and practices, and the second two would think and 
work almost identically. In these days there is rather more thinking and 
comparison and a resulting improvement in granulation, from a commercial 
as well as a technical point of view. Wheat splitting is done by a dress that 
nips and cracks the berry ; flouring at one operation, by fast-running stones 
close together and having one-third their area in furrows ; " middlings mak- 
ing," by slower stones farther apart and furrowed over two-thirds their sur- 
face ; middlings flouring, by shallow furrows ; and bran dressing, by stones 
having less furrow surface than for granulating.* 

The variable elements in granulation and grinding by burrs, are diameter, 
speed, quality of stone, and dress. 

* See Chapter XXIV. on Various Millstone Dresses ; also, Chapter XXXI. on Systems or Processes. 



358 



OPERATION OF THE BURRS. 



Diameter of Burrs. — When we consider the question of the diameter 
of the stones, we must remember, that all conditions cannot be equal, when 
we have a comparison to make. If stones of different diameters have the 
same rotation speed, they will have different rim-speeds ; if their diameters 
are as three to two, their gross areas will be as nine to four. 

A five-foot burr has 15.7 feet periphery, and 19.635 square feet area, 
exclusive of the eye. A three-foot stone has 9.424 feet circumference, and 
7.068 square feet area. Deducting from the first, 18 inches for eye; and 
from the second, 12 inches eye, we have left 17.868 square feet for the large 
stone, and 6.2826 square feet for the small one. 

At 200 revolutions the three-foot stone would have a rim-speed of 1884 
feet per minute. To get the same rim-speed, the five-foot stone would need 
to run only f of 200= 120 turns. (See table of rim-speeds, etc.) With 
the same rim-speeds it will be seen that the grinding areas per minute are 
widely different. 17.868 x 120= 2144.16 square feet per minute, that will 
pass a given radius ; 6.2826 x 200 = 1256.52 square feet in the same time. 

Hence, equalizing the rim-speeds, will not equalize the areas passing. 

Between a few large stones and more small ones of the same actual 
capacity, as proved by actual work done at such speeds for each, as will 
best suit all the conditions (or as many of them as can be suited). The 
author, leaves the reader to exercise judgment — merely saying that large 
stones are heavier ; hence, cause more springing and wear ; the time lost in 
dressing one run at a time is proportionately greater ; it is less convenient, 
and more expensive to have a set of spare stones, and to change the dress 
or speed for a particular purpose. 

The following table gives the circumferences of millstones in feet and in 
inches ; their areas in square inches ; and their rim-speed, in feet per minute 
at various rates of rotation. It will be noticed that the circumferences and 
areas are more fully filled out than the rim-speeds : 

TABLE OF RIM-SPEEDS IN FEET PER MINUTE. 



sx 


u 




^• 


O 















a 




a> 


c 




Revolutions 


per Minute. 




u 

s 

at 


W (0 


Is 

U C 


T 

i 


(U 










100 


130 


140 


160 


180 


200 


Q 


b 


<~ 


5 


b 














18 


56.55 


254-47 


1-5 


4-71 


471 


565 


660 


754 


848 


942 


20 


62.83 


314-6 


1.667 


5-24 














22 


69 12 


380.18 


1-833 


5-76 


. , 












24 


75-40 


452.39 


2. 


6.28 


628 


754 


910 


1005 


1131 


1256 


26 


81.68 


530.93 


2.167 


6.81 






. . 




, . 




28 


87.96 


615-75 


2-333 


7-33 






. . 








30 


94-25 


706 . 86 


2-5 


7.85 


785 


943 


HOC 


1257 


1414 


1570 


32 


100.53 


804.25 


2.667 


8-37 


. . 




. , 


. . 






34 


106.81 


907.92 


2.833 


8.90 






. . 








36 


113.09 


1017.9 


3- 


9.42 




1131 


I2I9 


1508 


1696 


1884 


38 


119.38 


1134-I 


3.167 


9.96 








. . 






40 


125.66 


1256.6 


3-333 


10.47 














42 


131-95 


1385-4 


3-5 


II. 


942 


1219 


1539 


1760 


1879 


2199 


44 


138.23 


1520.5 


3-607 


11.52 














48 


150.80 


1809.6 


4- 


12.57 


1257 


1505 


1759 


201 1 


2264 


2513 


54 


169.65 


2290.2 


4-5 


14.14 


I4I4 


1696 


2262 




^. . 




60 


188.50 


2827.4 


5 


15-71 


I57I 


1885 


2042 









DIAMETER OF BURRS— SPEED, ETC. 359 

Speed of Grinding. — Slow grinding makes more middlings than fast. 
A close stone should not be clogged with grain under any circumstances, or 
it will grind warm. In fact, no stone should be allowed to be clogged. 

Perhaps the greatest evil in milling is fast grinding. Flour once killed by 
over-heating can never be restored by any means. 

There is more flour ruined by being under the stone too long than by 
passing under it too quickly. 

"A four-foot stone for custom grinding should run from 150 to 160 on 
wheat, and not over 175 or 180 on corn. For merchant work 140 to 150." 

There seems to be a tendency to fast grinding, which is doing harm to 
most of the systems now in use. 

The usual problem being to get all the middlings possible, the miller 
should choose such conditions as will, other things being equal, make the 
yield of middlings high and the quality round and sharp. And the speed 
must not be left unconsidered. 

Slow grinding generally makes more and sharper middlings than faster 
grinding does. 

Dress and duality of Stone. — These questions have been more 
fully considered in the proper chapters, to which the reader is referred. 

Troubles in Grinding — Are many ; the reasons more numerous. In 
the matter of warm grinding, there are many causes of this difficulty, one of 
which is clogging. The miller must not expect too much of a stone. In the 
South there is liability to fast grinding, which destroys the little gluten the 
Southern wheat has got. 

Clogging is another evil that the miller has to contend against. If the 
spots are too small or of too slight pitch, or so arranged that in clogging 
the matter cannot be got out or jarred loose, there will always be more 
or less trouble, and this trouble might have been avoided in the beginning 
by proper attention to size, pitch, etc. 

So long as the stone grinds right, it makes no difference whether it rises 
or falls or not. It is the expansion of the spindle that raises the runner at 
first, but if the heat reaches the burr and expands that also, the stone is 
somewhat lowered. The expansion of the stone itself tends to bring the 
burrs together. The stone may be lifted by the expansion of the burr, 
if this latter be too tight or gets dry. 

The mill spindle should be kept well oiled, because not only does the in- 
creased friction necessitate a greater amount of power to drive the stones, 
but the spindle itself becomes abraded, and may heat so as to stick in the 
step. This often occurs. 

Some men have no end of trouble with their purification, and others none 
at all, the machine being just the same. The cause of this is the condition 
of the middlings. If you have flat irregular middlings of all sizes, you must 
expect to have trouble in their purification, especially if your mill be too 
small to make it economical to grade. Maxim : Have round granular mid- 
dlings. Then the question comes up. How can you have them in this condi- 
tion ? And the answer to that question is. By having the stones m good face, 
well balanced, the spindle trammed, the furrows in proper condition and 



360 OPERATION OF THE BURRS. 

enough of them. The wheat must be thoroughly cleaned and free from 
foreign substances. The burrs must not run too fast. Now, flat irregular 
middlings are caused by the opposite of any one of these conditions, except 
it may be grain cleaning, and even that has an influence on the middlings. 

There are mills where the purifier has not yet entered, and of course the 
proprietors are apt to "get left" in the matter of quantity and quality, 
especially the latter, and he must do his best to get good results without a 
purifier. 

In order to get middlings in the proper condition without grading, and 
without too much dusting, etc., the stones must be adapted to the work to be 
done. They require the greatest care, not only in getting them ready to run 
on middlings, but in keeping them fit to do this daily work. 

The middlings stones should be the sharpest and keenest in the mill. 

Soft wheat should, when practicable, be ground in fine clear weather 
In the spring, wheat is harder to grind than at any other time, because 
a new fermentation takes place. It is not a fermentation ; it is a natural 
swelling of the germ in the germinating season. 

The Quality of Burr Flour — Varies as a matter of course. Al- 
though color ought to be one of the last things to be considered the prime 
point in flour, yet, as things are now, it is a desideratum, and we must make 
flour to suit the market, as we cannot make the market suit the flour. 

Sometimes we see two widely differing lots of flour made from the same 
grade and quantity of wheat and in two mills built almost exactly alike. But 
there are many reasons for this difference. 

The difference in color in flour made in different mills may be owing to 
the difference in the dress, in the grit of the stone, or in the speed of the 
burr. It may be poorly bolted in one and well in the other. 

" Flour made by stones has a darker shade than that made by rollers, even 
if the same clean middlings are used in both operations. Differentially- 
speeded rollers give yellower flour than equally-speeded rollers, chilled iror. 
more yellowish than porcelain, and unventilated burrs than ventilated. This 
cannot be attributed to heating during grinding, as yellow flour, if pounded 
in an agate mortar, becomes white." 

One trouble that the miller often has with the farmer is that the latter 
often brings foul wheat and demands the highest yield. 

Bread made from granular flour is said to keep moist much longer than 
that which is from less granular. 



CHAPTER XXVII. 

COOLING THE CHOP. 

Millstone Ventilation — High-Pressure Aspiration. 

Millstone Ventilation. — Rapid feed or too great pressure causes 
heating of the chop. Even with the best dress and the greatest care there 
will always be some heating and wasting, the waste and flour dust together 
form a paste on the sides of the hoop in the elevator pipes and conveyor 
screws and bolting machines, rotting the wood and clogging the silk, besides 
wasting flour. To prevent this a current of air is used, drawn from the cir- 
cumference of the burrs. As long as the burrs remain cool they remain sharp, 
and the longer they are sharp the longer they will produce a sharp, white 
flour. Cool grinding develops the quality of the flour. The cooler the burrs 
the more they grind. The cooler and drier the flour the more the bolts can 
handle. 

The injury from the heating of chop grows proportionately with the rate 
of feed and pressure, the present tendency being to rapid work. Heating is 
more common than usual. While it may be reduced by careful dressing of 
the burrs, yet even with the best dress this will not do away with the evil of 
sweat, which in damp or cold weather settles on the sides of the millstone 
hoop, in the elevator pipes, conveyors and bolts, forming with the flour dust 
a paste that soils the cloth, sours and infects the air, rots the wood, clogs the 
silks and passages of the machines, and wastes flour dust. 

Attempts have been made to blow air from the millstone eye, between the 
two stones, but this gave trouble by filling the mill with flour dust. At pres- 
ent suction is substituted for blast, the air being drawn at the skirt. As 
ordinarily but imperfectly applied the construction is about as follows : a 
short leather hose hangs from the top of the hoop and either slides on the 
surface of the upper stone, or fits loosely into the mill ring fastened to the 
stone. From the top of the hoop there is a wooden or sheet-metal pipe to 
the main exhaust pipe which leads into the dust room. The demerits of the 
system are : the leather hose soon wears out from friction with the stone or 
ring ; a strong current of air cannot be applied by reason of imperfect fit- 
tings ; too great loss of flour dust ; and sweating, while it is barely prevented 
in the hoppers and conveyors, is not obviated in the dust room and dust 
pipes. In the last we find the walls covered with paste. Furthermore, there 
is great danger of explosion by reason of the exhaust pipes and dust rooms 
being constantly filled with an explosive mixture of fine dust and air, liable 
to be ignited by a piece of iron accidentally entering the burrs. Mills have 
frequently been wrecked from this cause. 



362 



COOLING THE CHOP. 



Bovill, in England, lessened the loss of flour dust by making a cloth par- 
tition in the dust room ; and Perigault saved considerable flour by leading 
the dusty current through a room having several partitions, which, rapidly 
changing the direction of the current, causes a deposit of the flour. To 
lessen the formation of paste, double walls were provided for the dust pipes 
and dust rooms, and even steam-heating pipes supplied. 

High-Pressure Aspiration. — The Behrns & Brehmer high-pressure 
aspiration device, illustrated herewith, is intended to afford perfect cooling, ven- 
tilation and freedom from dust. The following description will be readily un- 




FiG. 260. — Behrns-Brehmer Exhaust. 



derstood, reference being made to Fig. 260. In this instance, cc and dd 
represent the stones, the upper one being the runner, and bb the grinding^ 
surfaces. A fan exhausts the air through the pipe, a, from the millstone hoop, 
while fresh air re-enters through the eye of the millstone and passes between 
the grinding surfaces, as shown by the direction of the arrows in the engrav- 
ing. In order to make the supply current of fresh air as strong as possible, 
the hoop is made air-tight, and suitable connections and fittings are employed 
for the inlet as well as the openings of the chop discharge. For the inlet this 
is accomplished by means of two V-shaped cast-iron rings, well fitted together. 
The lower ring, h, is fastened to the running stone, while the upper one, /, is 
riveted to a leather cylinder suspended from the top of the hoop. A small 
chain fastened to the side of the upper ring prevents it from turning. 
The discharge opening prevents likewise the entrance of air at that point 
by means of the flap valve, g, as well as by the chop itself, which is 



HIGH-PRESSURE ASPIRATION. 



363 



pressed by the revolving screw, s, downward through the inclined part of 
the discharge pipe, and forn:is there an air-tight mass while the valve 
g is held open. By this means it becomes possible to draw a strong current 
of air through the grinding surfaces of the burrs, which is designed to keep 
the meal or chop perfectly cool during the process of grinding. It will be 
readily seen that such a strong air-current must necessarily carry with it a 
considerable quantity of flour dust, which would find its way through the 
exhaust fan unless provided against. In order to retain this flour dust within 
the hoop, the following device is applied : over a light iron framework, ni, is 
stretched and laced up in zigzag shape, a cloth of long-haired flannel. The 
frame, if suspended by three hooks under the top of the curb, and the flannel 




Fig. 261. — Behrns-Brehmee Exhaust. 



is tacked loosely, but dust-tight, against the top, at the outer and inner diam- 
eters of the frame. The nature and texture of the cloth are such, that 
although it detains every particle of flour dust, it allows all the warm air and 
the vapor generated by the dampness of the grain to pass through freely. 
The dust, therefore, gathers under the cloth, from which it is loosened and 
drops into the chop by slightly tapping the pin, /, at occasional intervals, the 
suction valve, r, being closed for a moment to allow the dust to drop off freely. 
The condensation of the vapor within the hoop, as well as the choking of the 
dust-catcher, is prevented by lining the entire hoop with a non-conductor, o, 
composed of felt, and which is covered over with galvanized sheet-iron. 
The upper curved part of the exhaust pipe, a, is also protected in the same 
manner, so that the condensation can commence only when its effect will be 
harmless. The vapor, on being condensed into water, will pass with the air- 
current through the exhaust fan and thence to the open air. A double 
vacuum gauge, ^, is placed on the top of the curb or hoop, and shows the 
rarefaction of the air both inside and outside the dust-catcher. The time 

24 



364 



COOLING THE CHOP. 



when the dust should be taken off is thus indicated. The intensity of the 
current of air, which may be regulated by the check valve, ;-, is also accu- 
rately determined by the vacuum gauge q. The advantages which are ob- 
tained by this invention are numerous and important. The old method of 
ventilation permitted only a moderate current of air to be passed between 
the stones, on account of the great loss of flour dust incurred by a strong 
current ; but with the use of this aspiration, as strong a current of air as could 
possibly be desired for cool grinding is easily produced, and is not attended 
with the loss of a particle of flour dust. It is also evident that by its use 
the capacity of a mill can be considerably increased. In preventing the con- 
densation of vapor, this apparatus causes the formation of paste to cease, 
and no trouble from this source with conveyors, elevators and bolting cloth 




Fig. 262.— Behrns-Brehmer Exhaust. 



is experienced in the mills where this ventilation is employed, besides ob- 
viating the fires and explosions arising from the accumulation of flour 
dust of the former system. All of the ventilating apparatus for one mill are 
connected with only one exhaust fan, no matter how many pairs of burrs are 
to be ventilated. 

The meal discharge valve of Fig. 261 is a wooden flap valve held closed 
by its weight and the suction of the exhaust. The weight of the meal will 
force it open and the meal will pass out without permitting the air to enter. 

The discharge valve shown in Fig. 262 is made of cast iron, and contains 
a conveyer screw similar to that shown in Fig. 260, but occupying a horizon- 
tal position. By it the meal is forced against an iron flap valve which pre- 
vents the air from entering the curb through the meal discharge spout. In 
both cases the chop, itself accumulating around the flap valve, forms a very 
effectual packing, and prevents a leaking of the valve. When the cast-iron 
valve is used a greater degree of exhaust can be attained than with the sim- 



HIGH-PRESSURE ASPIRATION. 365 

pie flap valve, as the weight of the meal would not be sufficient to open the 
valve when the flap valve is held closed by a strong suction. But with the aid 
of the screw discharge valve the discharge valve can be opened against any 
amount of suction. Lately an addition has been made by Mr. Behrns in the 
shape of an automatic rapper. At a trifling addition of price an apparatus 
will be furnished which at intervals will automatically close the exhaust valve, 
r, P"ig. 260, and cause a hammer placed over the pin e, to strike several 
blows against that pin, when the valve will be reopened again. 

The old-fashioned way of cooling the chop by having the hopper boy or 
a cooling room is done away with. The disadvantage of leaving a cooling 
room as a reservoir into which meal is run all night and bolted next day, is 
that it requires double capacity for bolting and purifying, and also for 
regrinding middlings. The advantage of bolting as you grind is that 
you can see what you are doing and make a more even grade of flour. 
Whatever grade of flour you make be particular to make it even. 



CHAPTER XXVIII. 



ATTRITION BY AIR-BLAST. 



Attrition by Air-Blast, — In the device illustrated in Fig. 263 there 
are two triangular or fan-shaped sectors, a and b, placed so as almost to 
touch at the outer edges and to be about a quarter of an inch apart at the 
apex, the edges being closed by the adjacent surfaces. All of these places 
are corrugated with ranges of ribs having cutting edges, standing toward the 
apex. At the apex there is a chamber, ^, formed between the plates, between 




Fig. 263. — Fan-Blast Attrition JIill. 



which the induction tube, f, is connected ; /^ is a grain hopper, with a regu- 
lating slide, /, and tube, /, opening into the tube /. Air under a pressure of 
250 pounds to the square inch is admitted to the pipe, 711, and draws the grain 
through the induction tube, /", and forces it powerfully between the roughened 
converging plates, a, b; crushing, spreading and driving forward the grain 
until the flour is blown out at the narrow opening between the outer edges of 
the plates a and b. It is preferable that the plates should be of steel or chilled 
cast iron. The area placed between the plates near the apex corresponds 
with the area of the long narrow opening at the outer edges of the plates. 

This process seems to be operated exclusively by a company making 
health foods. The decortication effected by it is surprising in its cleanness. 



CHAPTER XXIX. 

IRON DISC MILLS. 

Iron Disc Mills — Raymond Brothers' Mill — Jonathan Mills' Disc Machines. 

Iron Disc Mills. — There are many classes of work where there is 
demanded great capacity, together with high speed and low cost of mill, and 
where there is no skilled labor required (or even attainable) for the purpose 




/ 



KiG. 264. 

of dressing, mounting and running the apparatus. Such mills are very fre- 
quently needed at a great distance from repair shops or supply houses, and 
must consequently have some provision for repairing damage or breakage by 



368 



IRON DISC MILLS. 



duplicate grinding surfaces, always at hand. It is, also, advantageous to be 
able to vary the character of the material ground, without tedious or costly 
change of dress. To meet such cases, the iron disc mill comes in admirably. 
Raymond Brotliers' Mill. — In the iron disc vertical grinding mill. 
Fig. 264, patented by George and Albert Raymond,* December 30, 1879, there 
are many features which are at once interesting and valuable. There have 
been many metallic grinders made, all of which have endeavored to produce 
a grinding surface of metal which would retain sharp cutting edges and wear 
for a long time without being resharpened. Some are cast with the dress 
upon their face, the face being chilled ; but in these mills the cutting edges 
become rounded, and the metal gets softer as the hard chilled face wears 
away. There are some which have steel strips or blades inserted in the body 
and properly backed. To make a cheap self-sharpening grinding surface the 




Fig. 265. — Disc of R.'^ymond Mill. 

Raymonds make the body of soft iron and the cutting portions of chilled 
iron (Fig. 265). By this arrangement the soft metal wears away more rapidly 
than the harder metal, leaving the latter exposed. (We find this same arrange- 
ment in the tooth of the common squirrel ; the soft body at the back wearing 
away and leaving the strongly enameled front of the tooth sharp and cutting.) 
In making the Raymond discs there is a soft-iron body formed by casting, 
leaving spaces for the subsequent reception of the hard metal After this 
soft body has become cold it is placed face down in the mold and used as a 
chill, molten iron being poured in it to form hard grinding or cutting portions. 
These grinding discs are cheap, and have a wonderful capacity. Visitors to 
the Cincinnati Millers' exposition of 1880 will remember a corn mill and this 
principle in one of the galleries. One ingenious feature in the mill proper 
is the insertion of a wooden pin in the coupling, which pin will break off if 
any hard foreign body (as a nail) gets between the discs, thus preventing 
damage to the mill. Spare plates with different dress can be readily put in 
to suit different material, or to replace those which may become worn out. 



* Raymond Brothers, Waupan, Wis. 



JONATHAN MILLS' DISC MACHINES. 



369 



Jonathan Mills' Disc Machines. — It must not be supposed that 
the iron disc is limited in its usefulness to rough, fast milling, such as corn 
grinding. On the contrary, one class of iron disc mills has at a stride ad- 
vanced to a position entitling it to the most respectful consideration, as it 
effects the gradual reduction of wheat under the most advanced processes of 
high milling proper. 

The most prominent type of iron disc mills is that bearing the name of its 
persistent inventor, also attached to the process under which gradual reduc- 
tion by his iron discs is carried out. We describe it at length, as specially 
applied to degerminating and gradual reduction. 




Fig. 266. 

Iron disc mills are used not only for granulation and gradual reduction, 
but for removing the germ, the object being to take this out without injuring 
the bran or breaking down the berry. In order to effect this, it is desirable 
that the discs shall be driven upon a rigid axis and at a fi-xed distance apart, 
and that the grain fed to them shall be graded before splitting. For ordinary 
purposes it is sufficient that the wheat shall be graded into two classes, large 
and small. Fig. 266 shows a mill embodying these principles. 

Fig. 267 shows the face of the disc employed for degerminating; Fig. 
268 an enlarged view of the whole machine, vertically through the centre. 
For taking out the germ and some impurities, the discs are entirely of 
iron, sixteen inches in diameter, with marginal rounded corrugations, hav- 



370 



IRON DISC MILLS. 



ing absolutely smooth surfaces on a depressed bosom m each disc. The 
lower disc F, Fig. 268, is the runner, and the upper one E remains stationary, 
being provided with a central feed-opening in which there is a hopper, Fig. 
269. The bosom reaches to within a few inches of the skirt, so that the 
grain may have free passage in a horizontal position (or upon its side), but not 
otherwise. It will be remarked that this is just the reverse of the object to be 
attained in "ending " grain. The corrugations, V, of the skirt have a draft 
of about three inches, as shown in Figs. 267 and 272. Each ridge is about f 
inch wide at the skirt, and the inner ends slope at an easy incline to the level of 
the depressed bosom of the disc. The discs are shown in section in Fig. 270. 




Fig. 267. — Mills' Degerminator. 

It will be seen that the ridges are inclined upon one side as in a burr ; but 
this incline has a round summit, instead of the feather and track edges of a 
burr-stone. In the depressed bosom there are eight furrows, X, running 
from the inner ends of some of the breaking ridges, V, and terminating in the 
draft circle. In being intended merely to break open the wheat along its 
lengthwise crease, and let the germ and dirt drop out, there are no sharp 
angles or roughened surfaces which would tend to break the berry and cut 
the bran. There are suitable adjustment screws to set the lower disc at the 
proper distance from the upper, to suit the grain being split. The hand- 
wheel, G, serves for this adjustment. The machine runs at about 500 revolu- 
tions per minute. Centrifugal force and the leaders, X, cause the grain to 
run horizontally into the depressions between the ridges at the skirt. The 
ideal splitting is as shown in Figs. 270 and 271. 




Fig. 268. -Enlarged Partial Section of Mills' Machine. 




Fig. 269. — General Section of Mills' Machine. 



372 



IRON DISC MILLS. 



Substantially the same apparatus is employed for breaking down the 
grain, there being only some variation in the dress, adjustment, speed, etc. 




Fig. 270. — Ideal Action of Discs. 




Fig. 27J.— Ideal Splitting and Degermination. 




Fig. 272. — Mills' Reduction Disc. 

Fig. 272 shows the face of the reduction disc. These machines are manufac- 
tured by Chisholm Brothers, Chicago, 111. 



CHAPTER XXX. 

DETAILS OF DIFFERENT TYPES OF BURR 

MILLS. 



Classification of Mills. — Usual Type of Mill. — Munson's Geared Under-Runner Mill. — Munson's 

Portable Mill Spindle. — Plantation Mills. 

Classification of Mills. — Mills, that is, the machines or frames, are 
classified according as the burr faces are vertical or horizontal, into " verti- 
cal " or " horizontal." The distinctions, " upper-runner," " under-runner " 
and vertical also apply to the whole frame, as do those of "oscillating" and 
"stiff" drive. In addition to this, the distinctions of "belted" and 




Fig. 273. 

"geared " mills come in. The most usual type up to the present day seems 
to be the oscillating upper-runner geared mill, belt-drive coming more and 
more into use. 

Usual Type of Mill. — Fig. 273 shows a common type of mill, having 
stones from three to five feet diameter, and running at from 1,759 to 2,264 



374 



DETAILS OF DIFFERENT TYPES OF BURR MILLS. 



feet per minute rim-speed, corresponding to 140 lo 180 turns per minute for 
a four-foot stone. The capacity of such a four-foot stone is from six to 
fifteen bushels of wheat per hour, depending on the speed and dress of the 
stone and the quality desired in the product, and consuming an amount of 
power not yet properly estimated. 

Munson's Geared Under-Runner Mill.— Fig. 274 represents 
in lengthwise vertical section a double-geared under-runner mill, made by 
Munson Brothers, Utica, N. Y. 

A represents a cast-iron frame, on the upper part of which is a cylindrical 
shell, B, to receive the runner or under-stone, C This shell is of larger 




Fig. 274. 



dimensions than the stone, C, so as to leave a space, a, all around and under- 
neath the stone, C. The shell, B, has its upper edge made perfectly smooth 
and even, so that all parts of its surface will be in the same plane. The shell is 
cast in the same piece with the frame, A. In the lower part of the frame 
there is placed a horizontal driving shaft, D, which has a bevel wheel, E, 
secured to its end. This wheel gears into a bevel pinion, a, on a spindle, F, 
the lower end of which is stepped in a socket, b, the upper end of which has 
a flange, c, around it. This socket is fitted within an adjustable box, </, which 
rests upon a lever supported by a nut and screw, by which means the stones 
may be made to run at a greater or less distance from each other to vary the 
fineness of the flour. The spindle, F, is provided with a collar, I, which is 



MUNSON'S GEARED UNDER-RUNNER MILL. 



375 



fitted within a box, J, attached to the underside of the shell. This box is 
of cylindrical form, concentric with the shell, and within it there are placed 
bearings, h, which are adjusted snugly against the collar by keys, screws or 
other means. The collar is hollow and opened at its lower end, having a 
space, /, all around between it and the spindle, as shown at/. The box is 
provided with a central vertical tube, k, around which the collar works, the 
tube passing up between the collar and the body of the spindle. The upper 
part of the collar is perforated with holes, /, which are just above the bear- 
ings, h, and above the upper end of the tube, k. K is a tube which extends 
along underneath the shell, and communicates with the upper part of the 
box, this tube, K, forms a means of supplying the box with oil at any time. 




Fig. 275. — Ui'PER OR Bed-Stone. 



The collar within the box forms the bearing surface of the spindle. The 
box is covered within the shell by the cap, ;«, having a circular aperture in 
its centre to allow the spindle to pass through, this aperture having a flange, 
n, around it, covered by a cap, 0, on the spindle. On the upper end of the 
spindle there is placed a clearer, L. This clearer is formed of two arms, j?)^, 
attached to an eye, q, which is fitted on the spindle and secured thereto by a 
feather and groove. The arms of the clearer extend nearly to the side of 
the shell. M represents the driver, which is fitted on the upper part of the 
spindle, and like the clearer is secured to the spindle by a feather and groove. 
The driver rests on the eye of the clearer, and the driver has two arms, rr, 
projecting from its opposite side. The arms are rounded at their face sides 
or bearing surfaces, the curvature being in a vertical plane, as shown at s. The 
arms of the driver fit within recesses, //, of a shell, N, which is secured con- 
centrically within the runner, and has a pendant bearing, w, which rests upon 
the apex of the spindle. The damsel, O, is attached to the upper surface of the 
shell, N. P is a cast metal cylindrical box, in which the upper stone, Q, is 
secured by set screws, wiv. This box is turned true at its lower part so that 



376 



DETAILS OF DIFFERENT TYPES OF BURR MILLS. 



it may fit into the shell, the box being provided with a shoulder or flange, <2', 
all around it, which flange is parallel with the lower edge of the box, P. The 
stone, Q, has an eye, ^', made in it centrally, and the box, P, is secured in 
proper position by means of screw rods, c , and nuts, d\ the rods, c, being 
attached at the shell, and passing through eyes, e , at the outer side of box, 
P. On the box, P, a hopper frame, R, is placed, containing the hopper, S, 
and shoe,/', which may be arranged as usual. It will be seen from the above 
description that the runner, C, will, in consequence of the arrangement of 
the driver, M, relatively with the apex of the spindle, F', be allowed to ad- 




FiG. 276.— Spindle for Portable Mills. 



just itself to the stone, Q, so that the parallelism of the faces of the two 
stones may be preserved as the stone, C, rotates. This arrangement, to wit : 
the having of the apex of the spindle in line with the bearing surfaces of the 
arms, rr, of the driver, admits of a universal joint movement of the stone, 
C, an effect which cannot be attained in the ordinary arrangement. This 
invention also enables the spindle to be always kept properly lubricated, as 
oil may be poured into the box, J, at any time, and the oil within the box is 
retained therein, in consequence of the perforations, /, in the upper part of 
the collar, I. These perforations cause the oil, which may have a tendency 
to rise in the space between the tube, k, and the collar, I, to pass the holes,/, 
into the box, instead of passing over the tube, k., which extends above 
the holes of perforations, /. This is an importat feature, as it effectually 



\ 



MUNSON'S PORTABLE MILL SPINDLE. 



377 



prevents the escape of the oil from the box, J, when the latter is not over 
supplied. 

The burrs are furnished in duplicate to suit those who run constantly, 
so that when one pair is out for sharpening the duplicates can be used. 

Munson's Portable Mill Spindle, — "Some of the so-called porta- 
ble mills answer very well on coarse grains and coarse grinding, but for fine 
work they do not meet the demands of the trade ; they are constructed with- 
out regard to the tramming of the spindles or the importance of keeping them 
in their true working positions. The metal boxes, which are held up against 
the collar or the neck of spindles, are continually wearing out, and unless 
some provision is made whereby the spindles may be perfectly and accurately 





Fig. 277. — Kaestner Mill Closed. 



Fig. 278. — Dressing Burr of Kaestner Mill. 



adjusted, the work performed is of an inferior quality, and the loss of power 
by friction greatly increased. The curb of the mill, being cast in one piece, 
has its inside rim turned perfectly true, and by means of a tram-stick or index 
any deviation or any perceptible change in the position of the spindle, no 
matter how slight, can be easily detected and easily adjusted. The spindles 
are made of solid wrought iron or hammered iron, and are provided with in- 
serted solid steel points, ground in on a taper fit with emery and oil, making 
an absolutely perfect bearing, which maybe easily removed when injured. 
The neck or collar is forged solid on the spindle, and reamed out to fit 
within the bush ; inside the bush babbitt-metal boxes are placed, which are 
held up against the collar by set-screws. The bush is provided with a central 
vertical tube, around which the collar works, the tube passing up between the 
collar and the bottom of the spindle, the collar in the bush forming the bear- 
ing surface of the spindle. The bush is covered by a cap having a circular 
central opening, through which the spindle passes. The bush once filled 
with oil will keep the bearing of the spindle lubricated until the oil is ex- 
hausted or worn out, with no delays from over-heating, and with no loss of 



378 DETAILS OF DIFFERENT TYPES OF BURR MILLS. 

power by friction. These mills are constructed with the under-stone hung 
on a sensitive point or cockhead spindle, or they can be made with the 
under-stone rigid and stiff on the spindle." 

Plantation Mills. — These are generally vertical and are run at high 
speed. Being run by irregular power, they should have positive feed, so as 
to feed in exact proportion to the speed the burrs are to run, thus prevent- 
ing choking in the eye. Such a mill can be used handily in a saw-mill, where 
the motion is very irregular. A i6 or i8-inch mill, running 300 to 800 revo- 
lutions per minute, will grind five to ten bushels of corn per hour. 

The Kaestner Vertical Burr Mill.* — Figs. 277 and 278 have the 
runner in a wrought-iron shaft, running in self-oiling boxes. The runner is 
rigidly attached to the shaft, but the bed-stone has an oscillating attachment 
or universal joint, permitting its accommodation to foreign bodies, etc. The 
bed is attached to the frame by dovetailed slide-blocks, which can be moved 
forward and back. To put the stone in balance, there are two pins connected 
to these blocks, which are provided with rollers, working in connection with 
a universal collar attached to the frame at the back of the stone and forming 
the universal joint. The runner is put in working position by a steel point 
attached to the lighter lever and coming in contact with a corresponding 
steel point on the shaft. A spring attached to the lighter rod yields to the 
entrance of a foreign body and then presses the bed-stone to its work. The 
burrs may be held apart while feed is shut off, allowing them to run idle 
without throwing the belt off — an advantage which many appreciate, especi- 
ally in the South, and for farm and custom work. 

* Made by Chas. Kaestner & Co., 63 South Canal street, Chicago, 111. 



CHAPTER XXXI. 

SYSTEMS AND PROCESSES. 

Progress of Modern Milling — Hungarian Roller System — Why Hungarian System is Complicated — 
Details of 150-Barrel System — A 450-Barrel Roller Mill. 

Progress of Modern Milling. — Several causes have opened the 
way to the powerful and progressive movement of modern milling. Among 
these may be mentioned the increasing demand for high grades of flour free 
from bran and from woody fibre. The demand for this glutenous* middlings 
flour becomes larger from year to year, for two reasons : — society becomes 
more and more luxurious as the years roll on, and the idea that it is neces- 
sary to scour the intestines with irritating woody fibre is losing ground. 
Another cause for progress in milling in the old country is that the consump- 
tion of breadstuffs has increased by reason of increase of population, while 
harvests have steadily declined by reason of the withdrawing a large num- 
ber of workers from the fields, the ruining of harvest fields through the 
passage of armies over them, and the general impoverishing of the country 
necessarily dependent upon wars. While declining harvests stimulate the 
European miller to larger production and improved quality of flour, the 
opening out of the great American and Australian wheat fields, Avith their 
immense yields and exemption from expense for fertilizers, exert a powerful 
competition with transatlantic wheat growers. 

It is not only desirable, but necessary, that, as a matter of economy, the 
yield and quality of wheat flour shall be improved, the cost of manufacture 
lessened, and the less available kinds of wheat be brought into use ; and as 
a matter of business prudence each miller should keep as near as possible 
to the front rank in his trade. 

Competition, stimulated by ample rewards for successful invention, is 
fierce, intelligent, well organized, and backed with abundant capital ; hence 
systems, processes, and devices follow each other with wonderful rapidity 
and with marked and beneficial effects upon the rapidly advancing science of 
milling. 

There are, perhaps, few words more loosely applied than "system" and 
" process " as used in the milling art. The dictionaries draw no satisfactory 
line between them. They are used indiscriminately in about the same way 
as the word "continent," in reference to which latter we may say that some 
geographers divide the land on our earth's surface into two continents, some 
five, and some eight. In like manner, some say there are two processes, some 
five, and some a dozen or more. 

* Glutinous means, strictly, like glue ; glutenous means consisting wholly or in part of gluten. 

25 



380 SYSTEMS AND PROCESSES. 

In seeking a division line we may make it between the methods, and 
speak of "old" and "new" process as meaning whole wheat milling and 
middlings milling, no matter by what machines effected ; we may speak of 
"low" and "high" milling to represent the same distinction, and we 
may divide the latter into "single reduction" and "gradual reduction" 
processes. We may ignore the question of the operation, or the flow of 
material, and mark out our systems according to the granulation devices, as 
the "roller system," the "Jones system," the "Jonathan Mills system," etc. 
The term " Hungarian system" is loosely applied to roller middlings milling 
by gradual reduction, whereas the original Hungarian system was mid- 
dlings milling by gradual reduction with burrs. As both " high " and 
" low " milling are effected with rollers the matter is further complicated ; 
and when we come to consider that the various operations in any one 
method as a whole — say middlings milling — may be effected by combina- 
tions of successive devices, the entire matter beggars description. Thus 
the breaks may be done on rolls or on burrs ; the middlings reduction has 
equal choice, and the bran dressing may be by burrs, rolls, beaters, or brush 
machines. 

The author, then, declines to commit himself to a definite reply to the 
oft-asked query, " How many systems or processes are there ?" because the 
words system and process are ambiguous, interchangeable, and indiscrimi- 
nately applied, and the methods of making flour from wheat are so various 
that there are scarcely two mills in a hundred (if there are that many) 
in which the methods are the same. It may be said in a general way 
that popular usage seems to limit the words " old process " to low milling by 
burrs; "new process" to the use of burrs to make a large proportion of 
middlings, separately floured on burrs ; and " roller system " and " Hunga- 
rian system " to middlings working by gradual reduction with rolls, followed 
by middlings flouring with rolls. 

There is no good in getting carried away by any one system and being in 
such a hurry to get it in operation that you have no time to consider all the 
conditions. Study it well first. 

The harder the wheat is the better high grinding pays in connection with 
the roller system. 

The original high grinding system was commenced in the mills of the 
Danube, most of them two or three pair mills, averaging under five pairs, and 
all driven by water-power. 

In some Continental mills the gradual reduction system became so popular 
that in mills not having enough stones for the complete process to go on con- 
tinuously, they first broke the wheat, dressed and sorted it, then redressed 
and resorted it until the process was complete. 

Let it be the maxim that in the proper breaking of the wheat before 
grinding lies the secret of making white wheat flour. 

Otto MuUer states that 2.7 to 5.5 cvvt. of wheat is ground on roller-mills 
for each horse-power, against 3.3 cwt. by millstones. Oexle is very frank 
about the roller system. He says ; " The harder the wheat the greater 
the need for gradual reduction, and the softer it is the better the results 



HUNGARIAN ROLLER SYSTEM. 881 

of flat grinding. And for the softest wheats, like some of those of the South- 
ern States, flat milling is perhaps as good a way of grinding as any." 

Hungarian Roller System. — The leading features of this system 
are as follows : 

1. Systematic separation, scouring and brushing. In this it does not 
differ from any other good system of milling, 

2. Wheat granulation by grooved chilled-iron rollers, employing at least 
five breaks, and rolls having from eight to thirty grooves to the inch, making 
but little flour and leaving the bran finished. 

3. Separation of the light chaff from the breaks by aspirators. 

4. Thorough and systematic grading and purifying the middlings by 
purifiers. 

5. Sizing the large middlings by equally-speeded smooth chilled-iron 
rolls, thus reducing their size and taking out germs and bran specks. 

6. Reducing the fine clean middlings to flour by differentially-speeded 
porcelain biscuit rollers. 

7. Full and complete bolting after each of the above. 

After cleaning, the wheat is sent to a grading reel to be separated into 
two or three sizes, to secure proper action in the ending stones, which would 
not otherwise touch the small grains, and would take too much off the 
large. 

Cracking may be done on smooth rolls, and is really a cleaning operation, 
because the grains open out at the crease, setting free some dirt which the 
brusher has failed to reach, and the germ is dropped out or loosened. Crack- 
ing yields about one per cent, of fine material, one half being germ and dirty 
flour, and the other inferior semolina. 

After the wire cylinder of the cracking mill, the wheat goes to the coarse 
fluted rolls. The number of flutes on the rolls varies from 300 to 900. 

By the first cracking of the wheat there are got ten products : coarse mid- 
dlings, No. o to No. 5, inclusive ; fine and coarse bran, fine middlings and 
first clean groats, which last get a second cracking. 

There are generally three grades of flutes : two coarse, one medium and 
one fine. Each roll pair is followed by a scalping reel to take out the detached 
flour and semolina. The ordinary miller will run the flour from all the fluted 
rolls into his silks with that from the smooth rolls, thus producing one straight 
grade of good color. The advanced miller will separate more or less the 
different granulations, and take the cream off the best for his first qualities. 
Some new process millers make middlings all the way from 000 to 9, which 
is a good example of how not to do it. 

At each stage of the cracking there is separation and purification. The 
bran goes into three grades of bran and several qualities of black flour. The 
final product of breaking is 6 to 12 per cent, of bakers' flour, 80 to 86 of 
unpurified middlings, and 7 to 8 of bran. The baker's flour and middlings 
pass together into the scalping-reel, and the middlings from the scalping- 
reel into the grader. This grader yields 30 per cent, of finished white mid- 
dlings, 20 per cent, of larger middlings not so white, and 35 of coarse and 
brown middlings. 



382 SYSTEMS AND PROCESSES. 

To separatf the middlings from the bran particles, either smooth rolls or 
very finely fluted rolls are used. These yield but little flour, but still each 
time the product should be scalped and the middlings graded. There is 
more middlings purification than in this country. Making the middlings into 
flour is the last and easiest operation. It is done on smooth differential 
rollers, and is a simple easy crushing. 

It is claimed that by this process there is over 50 per cent, of flour which 
would, if mixed, be better than new process, and the rest (leaving out 12 
per cent, of black flour) better than the wheat flour of the new process ; that 
25 per cent more flour is made by the same power, and the yield increased 
twenty pounds to the barrel. 

The First Roller Mill. — The first roller mill was started in Pesth, 
the building and business being changed from a foundry to a flouring 
mill. 

"Why the Hungarian System is Complicated. — The reason 
why the Hungarian system is so complicated may not at first be understood ; 
and to understand it at all, there must be taken into consideration the wheat, 
the climate, the soil and the habits of the people. 

The Hungarian wheat is so brittle that, if ground low, the flour would 
contain bran particles too fine to be bolted out. 

There are used in the Hungarian mills three kinds of wheat, the best, 
the Bariat, subdivided into two sorts, one very small and of dark skin, and 
very hard, growing on both sides of the Danube, from Pesth beyond the 
Theiss river. The Theiss wheat, growing between the rivers Theiss, Maros 
and Szamos, is larger, less brittle and a little lighter in color. The Austrian 
wheat is more tender than the Hungarian. 

The hardest wheat comes from Stuhlweissenburg, fifty miles from Pesth, 
the soil being black as coal and the country level. There is very little of 
this wheat. These three are generally mixed, the Temesvar to give semolina 
and middlings, the Debreczin to give more flour at once, and the Stuhl- 
weissenburg to improve them both in strength and color. The latter is of 
medium size, lighter skin than the other two and more tender, very hard, 
breaking well into semolina, and of the greatest whiteness inside. 

All through Austro-Hungary, Germany, Italy, and other Southern Euro- 
pean countries, brown bread is used in every house, white bread being used 
in small quantities only ; but there is great demand for Semmel, Kipfel, 
Bounzel, Bratzel and Salztanzel, all of best flour and of various shapes and 
sizes. Back as far as 1807 we find semolina made and sold as Wiener Gries. 
It was hand separated. 

There is, then, a demand and a market for several grades of flour, from 
eight to thirteen being made in some mills. In France the black flour and 
hard bread of Hungary and Austria would find little or no market, a pater- 
nal government regulating the quality and price of bread, the quality being 
almost uniformly high and the price reasonable. In America, where bread- 
making is so much less understood than in France, the laboring classes, while 
refusing to eat such " schwarzjne/il" a.?, satisfies the working population in 
South-eastern Europe, have not been educated up to eating the high-grade 



DETAILS OF ROLLER MILL. 383 

bread that the French " blouse " exacts, because such light crisp-crusted 
wholesome bread is attainable in few American cities, even at any price. 

Details of 150-Barrel Roller Mill. — The regular roller process 
has this disadvantage, that it cannot be operated in the small mills with 
which this country, more than others, abounds. In mills making less 
than 150 barrels per day it is not applicable.* Such a mill will take 
seven double sets of break-rolls, using one each on the first, second and 
fifth, and two each on the third and fourth ; two on germ middlings, two 
on coarse middlings, one on fine middlings, and one set of porcelain 
(biscuit) to clean up the fine tailings. This might be used in connection 
with two pairs of four-feet stones for fine middlings, and one for tailings and 
the other low grade flour. Passing through one set of 9x18 inch corru- 
gated rolls, with eight flutes to the inch, the product goes through the first 
scalping reel, not over six feet long, and clothed with No. 18 wire. What 
passes through this should go to a roll covered with No. 10 silk, to take out , 
the fine dark flour. The tailings from this reel will pass to the chop reels, there 
to meet similar material from all the breaks. The second break-rolls take 
the tailings from the first scalper ; they have twelve grooves per inch, because 
the material is finer. The second scalper should be clothed with No. 20 
wire. The tailings from this go to double sets of rolls for the third break, 
having sixteen groves per inch of circumference. There is more grading 
done on the third and fourth breaks than on the others. The fifth has little 
else to do but to clean the bran. It may be well to have two short scalping 
reels for the third break and two for the fourth, because this will pound the 
coarse stuff as it passes along. 

Flouring unpurified middlings by too much handling should be avoided. 
All that passes through the scalping reels should go to the chop reels. The 
fourth break-rolls should have twenty flutes to the inch, and the fourth scalper 
No. 24 wire. The fifth break may be on double rolls with twenty-four 
grooves, and this is followed by the bran-duster. The chest of this mill may 
have eight reels, four on each side. The upper ones may be clothed with 
No. o. The tailings from this, going to the germ rolls, and that which passes 
through to the two next reels below, clothed with No. 4. The tailings from 
these will be coarse middlings and should go to the purifiers. The flour and 
fine middlings passing through the cloth will go to the rolls below, which 
have the head clothed with No. 11 and the tail with No. 9. Some flour will 
pass through the No. 11, and the fine middlings will be dusted on the No. 9, 
' and should be sent to the purifiers as soon as possible. That which passes 
through the No. 9 should be sent along with that which was not free from 
specks from the No. 11 to the next reels below, clothed with No. 12. This 
takes out all the flour. The tailings from the No. 12 may go with the cut- 
off from the flour reels to a fine middlings machine, thence to the porcelain 
rolls, there not being enough to keep a pair of burrs busy. 

For the coarse middlings there should be three purifiers, one below the 

* Since writing the above, " concentrated roller mills" and "pony break-rolls" have been intro- 
duced, enabling gradual reduction by rolls to be carried out in part in small mills, say of fifty to one 
hundred barrels capacity per twenty-four hours. 



384 SYSTEMS AND PROCESSES, 

other ; the upper clothed with Nos. 4, 3, i and 00, in equal lengths, the tail- 
ings going to the shorts bin. The second and third machines may be clothed 
one number finer. The tailings from these should be sent to the low grade 
stones, the clean middlings going to the rolls for crushing. 

There are five parts of break-rolls, having respectively ten, twelve, four 
teen, sixteen and twenty grooves to the inch. 

After each of these breaks, the material passes through scalping reels 
clothed with wire and cloth. What tails through one scalping reel goes over 
to the following break. What passes through the first three scalping reels 
passes into a reel which we designate A, clothed with nine feet of No. o 
cloth at the head and five feet of No. 20 wire at the tail. The tailings from 
the reel pass between the fourth break-rolls at the same times as the third 
break. What passes through the fourth and fifth scalping reels goes into the 
reel B, clothed with twelve feet of No. 10 at the head and four feet of No. 00 
at the tail. What tails over from the fifth scalping reel passes between the 
bran rolls, having twenty-four corrugations to the inch, and then through a 
bran duster clothed with No. 22 wire, the bran going over to the bran bin, 
and the flour passing through reels which we will designate C and D, C being 
clothed with twelve feet of No. 12 cloth and four feet of No. 4, D being 
clothed with sixteen feet of No. 14 cloth. What goes through the head of 
the reel C, goes over as low grade. What passes through the tail end of reel 
C goes through a pair of sizing rolls, and then through reel D, after which it 
passes with that from the head of reel C into low grade. What passes 
through the head of reel A goes into reel E, clothed with twelve feet of No. 
9 or 10 cloth and four feet of No. 4. That which has come through the No. 
20 wire cloth (equals 0000 silk) goes to purifier No. i. That which passes 
from the head of reel B goes to a separate chest for bolting with what passes 
from reel E. What passes through the foot of reel B goes to purifier No. 4. 
What passes from the foot of reel E goes to purifier No. 3. The tailings from 
reel E go to purifier No. 2. The tailings from purifier No. i go to the bran 
rolls. The purified product from No. i goes through sizing rolls, then 
through twelve-feet reel F, clothed with eight feet of No. 10 and four feet of 
No. 00. The product from the head of reel F goes with that from the heads 
of reels E and B to a chest for bolting. The material from the foot of reel 
F goes over into purifier No. 2 with the tailings from reel E. The tailings 
from purifiers Nos. 2, 3, 4, 5 and 6 go through tailings rolls, and then over into 
the bran-dusting reel. The product of purifier No. 2 goes through sizing 
rolls, then into reel G, having eight feet of No. 10 and four feet of No. o. 
Material from the head of reel G goes into the bolting chest ; that from the 
foot goes into purifier No. 3 with the material from the foot of reel E. The 
products from purifiers go together through sizing rolls, then into reel H, hav- 
ing eight feet of No. 10 and four feet of No. o. The material from the head 
of this reel, H, passes over into the chest for bolting. That from the foot of 
reel H goes into the head of purifier No. 5. The product of purifier No. 6 
goes through sizing rolls, which reduce it to flour. It then goes through 
reel K, clothed with twelve feet of No. 12, what dusts through going over 
into the chest for bolting and the tailings going over into the tailings rolls. 



MILLS' SYSTEM— JONES' SYSTEM. 385 

As I said before, all of the product from the tailings reels goes into the 
bran duster with the product from the bran reels. 

A 450-barrel roller mill should have six double sets of round corrugated 
rolls for breaking and bran dressing, three double sets of smooth iron, and 
one double set of fine scratch rolls for tailings. The purified middlings may 
be ground on four pairs of 30-inch under-runner middlings burrs, making 
350 revolutions. 

The Jonathan Mills System.* — The outlines of this system are 
as follows : 

1. Separation, scouring and brushing, as in any advanced method of 
milling. 

2. Wheat splitting and germ extraction by the chilled iron rounded-rib- 
bed "degerminator " disc shown in Fig. 267. (See chapter on Disc Milling.) 

3. Scalping out the germ and dirty break-flour loosened out by the de- 
germinating operation. 

4. A series of breaks or " gradual reductions " on round-ribbed chilled 
cast-iron reduction discs, shown in Fig. 272 of chapter on Disc Milling, each 
break being followed by 

5. Separation by wire scalping reels, suitably clothed, of the middlings, 
break-flour and broken wheat, and the last break proper being succeeded by 

6. Bran cleaning on suitable special machines. 

The sizing, grading and purification of the middlings, the bolting, &c., are 
devoid of special peculiarities ; the clothing and arrangement of the reels 
and purifiers are carefully suited to the material and with a view to the 
desired product. 

The writer regrets to omit the details of this process, as they are not yet 
(April I, 1882) made public, as are those of the Hungarian system and its 
modifications, the Allis, Stevens (Noye), &c.; he has seen it in operation 
at the mill of M. C. Dow & Son, Cleveland, O., and elsewhere. 

Jones System, t — The Jones system, which may be seen entirely 
carried out in the Linden Mills, Louisville, Ky., which were built and fitted 
specially to demonstrate it, has for its salient feature the employment of 
single cylindrical rolls working against a curved breast. The Jones ma- 
chine is shown in Fig. 281, page 388, and referred to under the head of 
Single Rolls. 

* Chisholm Bros., Chicago. + Jones, Ballard & Ballard, Louisville, Ky. 



CHAPTER XXXII. 

DETAILS OF ROLLERS AND FRAMES. 

Roller Milling — Varieties of Roller Machines — Number of Rolls, Single and Three High — Jones' 
Single Roll Frame — Roll Pairs — Method of Driving — Length of Rolls — Diameter of Rolls — Sur- 
face of Rolls — Materials of Rolls — Soft-Iron Rolls — Forms of Corrugations — Stevens' Patents 
— Number of Corrugations - Twist of Corrugations — Feed and Pressure — Axial Pressure — 
Differential Speed — Speed Ratios — Capacity of Round Rib Rolls — Yield from Roller Milling — 
Amount of Break Flour — Color —Strength of Roller Flour — Power Required by Rolls — Labor 
Required with Rolls — Coolness with Roll Work — Rolls on Soft Wheats— Break Rolls for Soft 
Wheats — Break Rolls for Mixed Wheats — Rolls on Middlings — Bran Cleaning by Rolls — Gray's 
Roller Frame. 

Roller Milling. — In considering roller or cylinder milling there are 
many things to be taken account of, viz., the number, relative diameter, rela- 
tive direction of rotation, speed, surface, and material of the rolls themselves, 
their uses, methods of mounting, driving, feeding and adjustment ; all these 
being considered in connection with a statement of the various processes of 
roller milling. 

Varieties of Roller Machines, — Rolls used in milling are either 
single, working against flat or concave stationary surfaces, or working against 
one or more rotating rolls. Where working together they may be of either 
equal or different diameters ; they may run toward each other or in opposite 
directions ; their speed may be the equal or unequal ; their surface may be 
ribbed, slightly rough, or polished ; they may be of steel, soft or chilled iron, 
porcelain (biscuit) granite, or syenite. They may be used for breaking, de- 
germing, flouring, sizing, or bran-dressing. The shaft of only one of the 
rolls may be driven, or both may have their shafts driven. Rolls may be 
used alone in connection with other equivalent apparatus for low, half high, 
or high milling. 

It will at once be seen that there are many combinations and variations 
of kinds of rolls possible. Many of these are in active operation with more 
or less success ; many more have been tried and abandoned. 

Single and Three High Rolls. — As regards the number of rolls 
working together, the single roll working against a breast is not in very ex- 
tended use, although for certain purposes it is doing good work, and may 
be made to do better, especially for the reduction of middlings to flour. 
Three high stands of rolls, in which a central roll works against one above 
it and one below it, these three taking the place of two pairs, are in suc- 
cessful operation, performing low milling, in Europe. They are not as yet 
common in America. 

Fig. 279 shows the action of a single roll against a plain surface, P, some- 
times used for cracking. There is but little contact, hence cool action ; but 



ROLLER MLLLING. 



387 



the capacity is naturally less than by any other method for a given peripheral 
speed. The greater the distance between m and n, the greater the friction ; 




Fig. 279. — SiNCLE Roll and Plane Breast. 



the greater the capacity (for a given fineness of grinding), and the less the 
pressure required. 




Fig. 280. — Single Roll against Concave. 



Fig. 280 gives a sectional view of the type of single roll against a concave, 
such as is made in stone by Jones. Ballard &: Ballard, of Louisville, Ky., and 



388 



DETAILS OF ROLLERS AAD FRAMES. 



in use in various parts of this country for reducing middlings. The machine 
is shown in Fig. 281, the adjustment being by hand-wheel and screw at each 
end of the frame. 

Roll Pairs. — The most common and successful type of roller machines, 
employed in more varieties and for more purposes than any other, is where 
both rolls are side by side, and are of the same diameter. Thus arranged, 
their work depends upon their material and surface, directions and speeds. 
The most common arrangement is where both rolls run toward each other ; 
in some cases the speed being equal, and in some, one roll running faster than 
the other. Where they run toward one another they have a squeezing or 




Fig. 281. — Jones' "Single Roll" Frame. 



crushing action, suitable for flattening the germ in middlings and for sizing 
the middlings themselves, although their action tends to cake soft material, 
which will then require to be disintegrated by special machinery which fol- 
lows it. 

Running in opposite directions, as though driven by an uncrossed belt, 
the " up " roll having a slower surface velocity than the " down," the action is 
to turn the material over and over while carrying it down and reducing it in 
size. This action is better produced by having both rolls run toward each 
other, as though by a crossed belt, but roll surface going faster than the other, 
so that the tendency to turn the material is the same, while the feed is faster 
and easier. Such rolls are used for breaking the grain, flouring the middlings 
and cleaning the bran. 

Method of Driving. — Where both rolls run in opposite directions, 
that is, downward and toward each other, one of them may be driven by 



ROLL PAIRS— DRIVING, ETC. 



389 



any desired means, and the other revolved by friction between it and the 
other roll, or the material being worked upon. Whefre both of them are to 
rotate in the same direction, that is, where they do not run toward each 
other in the grinding space, both shafts must be driven ; and this may be done 
by separate gears, by separate belts, by connecting gears, or by connecting 
belts. 

Connecting gears and connecting belts are the means most commonly 
adopted. Connecting gears have the advantage that the relative speed of 
rotation removes the same under all circumstances ; but at high speed they 
are apt to be noisy, unless specially adapted for this work, and to consume 
power. Connecting belts have the advantage that they run smoothly and 
without noise ; but there is some liability to lose the relative speed of rota- 
tion by slipping of the belts, unless they are very wide, and have consider- 




FiG. 282. — Roll Pair Running in Opposite Directions. 

able tension, with pulleys of larger diameter than are generally used for the 
purpose. 

Leugth. of HoUs. — Many roller manufacturers of to-day are trying to 
get extra capacity for their rolls by increasing their length ; but the difficulty 
of feeding them properly increases in proportion to their length, especially if 
the feed-roll be run too slow, as is generally the case. By the use of high- 
speed feed-rolls and special feeding devices, long rolls are now fed much 
more easily than formerly. The Stevens rolls are made from 15 to 30 inches 
in diameter, varying with the capacity of the mill. 

Diameter of Rolls. — The greater the diameter of the roll the greater 
the length of contact space, and the less the angle between the surface ; 
hence, the greater the friction on the material the easier the feed ; the less 
pressure required, the less power needed, and the greater the capacity for a 
given fineness of grinding, with all the other conditions equal. The 
" Stevens " (round nib) rolls are nine inches in diameter for all operations. 
Rolls less than eight inches in diameter seem unadapted to any of the 
operations in milling. 



390 



DETAILS OF ROLLERS AXD FRAMES. 



Surface of Rolls. — The surface of the rolls may (i) be ground, 
ribbed or fluted ; or (2) it may have a roughish surface or grain ; or (3) it 
may be smooth and jiolished. If ribbed, these ribs may {a) be parallel to 
tlie axis, or (/') they may have a spiral or twist given them. There may be 
(i) concave flutes in the convex cylindrical surface ; or (2) convex ribs 
raised upon the convex cylindrical surface ; or (3) they may partake of the 
nature of both these, and be waved or doubly rounded ; or (4) they may 
have the outline o£ the teeth of a wood rip-saw ; or (5) that of the teeth of a 




Fig. 283.— Action of Smooth Rolls. 

cross-cut saw ; or they may have any one of a number of other sections of 
rib, groove or flute, each having some special claims to our attention. 

Materials of Rolls. — Of the various materials used, chilled cast iron 
and porcelain biscuit are the most frequently employed ; the first either fluted 
or plain, and the second with a plain "grain " surface. Stone is apt to wear 
unevenly and too quickly. 

The influence of the material of the roll upon the pressure necessary to 
effect a given reduction, is shown in tests made with middlings and other 
materials, with rolls of cast iron, porcelain biscuit, granite, etc. It was found 
that to produce the same amount of middlings flour with cast-iron rolls as 
with porcelain, more than one-fourth more pressure was required. Dull 



CHARACTER OF ROLLS. 



391 



chilled-iron rolls work easier than smooth ones, although buyers seem to 
desire that new chilled rolls shall be polished. 

It is well known that the finer and sharper burrs are, the whiter the flour 
from them will be. For the same reason, porcelain rolls give a somewhat 
whiter flour than chilled iron. This greater whiteness is not due to a smaller 
percentage of bran particles, but to greater fineness of grinding ; nor is the 
dark color of flour at all due to particles of iron or carbon taken from the 
rolls, as supposed by many ; because paper manufacturers, who are as partic- 
ular as millers are about the whiteness of their product, employ rolls of the 
very same material as those used for flouring, and at a very much greater 
pressure. The darkening of flour by the material of iron or steel rolls is 
impossible. 

There are corrugated rolls made from stone, porcelain, and glass ; but they 
soon wear. 

It must be remembered that variations in the material of a smooth roll, and 
of the substance being operated on, cause variations in the coefficient of 
friction between the roll and that substance. The greater that friction the 
less areal pressure needed.. If c represents that coefficient of friction, and 
p the pressure, the power used will be equal to c times/. 

The following table, from Kick, shows the coefficients of friction of rolls 
of various kinds, on fine semolina (going through No. 7 gauze), and No. 2 
middlinsfs. 



Material of Roller. 


Coefficient of Friction on 


Hard Semolina. 


No. 2 Middlings. 


Chilled Iron, Polished, . 
"Matt," 
" Rifled, 
Porcelain Biscuit, . . . . 
Granite (" Matt" Surface), 
Syenite ("Matt") 


0.213 
0.287 
0.325 
. 404 
0.424 
0.445 


0-194 
0.268 
0.304 
0.364 
0.384 
0.404 



The coefficient of friction is evidently much greater with "matt" than 
with polished cast iron, and greater with porcelain than with either; being 
less with middlings than with semolina, all kinds of rolls ; and the proportion 
with different rolls running about the same Avith semolina as with middlings. 

Soft-Iron Rolls. — It is very often found that the regrinding of fine 
middlings cannot be finished with smooth polished roller surfaces, but that 
good results can be got by using for this purpose cast-iron rolls of homoge- 
neous and porous structure, which come more nearly to the condition of 
porcelain than the highly-polished chilled rolls which are on the market. 
When it comes to simply reducing large middlings or semolina to smaller 
size, any hard homogeneous material will do well enough. 

Forms of Corrugations. — The corrugations must be so arranged that 
they do not interlock. With a corrugated roll of hand rip-saw tooth section 
of grooves and differential speed, the action upon the grain is shearing or 
cutting instead of mashing or crushing, even although the cutting edges 



392 



DETAILS OF ROLLERS AND FRAMES. 



themselves become dull. This is the case so long as the fast roll has a speed 
at least double that of the slow one. Where the fast roll has a speed of less 
than twice that of the slow one, the action is no longer cutting or shearing, 
but crushing, mashing, or bruising. Where the rip-saw outline of tooth is 
used, the roll having the faster motion must have its teeth pointing down- 
ward in the grinding space, and the other upward. If, on the contrary, the 




Fig. 284.— Differentially Speeded Saw-Tooth Rolls. 



inverted teeth were to run faster than the others, then there would not be a 
cutting, but a crushing action. 

The finer the material to be ground, the finer the corrugations must be 
made for a given roll diameter. It might be said that the depth of the cor- 
rugations must be half (or less) the diameter of the particles to be reduced. 
With very short use the sharpness of the corrugations becomes lost, and mod- 
ern practice points to the employment of grooves intentionally rounded in 
section. 

Of course the great desideratum in a roller mill is to effect granulation 
without cutting the bran. It is claimed for the rounded ribs as against the saw 



FORMS OF CORRUGATIONS. 



393 



tooth that they roll the bran back and spill out the contents of the berry, and 
that even the cockle instead of being cut or crushed is held, the whole passing 
off in the final operation with the bran.* It is further claimed that the germ 
is neither cut nor broken, but that it is crushed, passing off in one operation 
from the scalper to be finally separated from the middlings. Just so far as 
these claims are borne out by actual commercial results, there is increase of 




Fig. 285. — Equally Speeded Saw-Tooth Rolls. 



yield and small proportion of low grade flour. It is claimed for a sharp 
tooth roll that it makes more middlings than the rounded rib ; but, on the 
other hand, for the rounded flutes that they make cleaner middlings than the 
"sharp cuts." There is this comparison between the sharp and the round 
tooth rolls and the millstone, that the one may be said to represent the old 
millstone dress in which there was a large proportion of cracked surface, and 
the other corresponds to the more modern idea of perfectly smooth surface 
of both the land and the furrows. 

One of the greatest drawbacks in the introduction of roll pairs is that 

* This latter claim, for any corrugated rolls, strikes the author as rather too strong. 



394 DETAILS OF ROLLERS AND FRAMES. 

while they render the hard spring wheat valuable for making better flour than 
that made from millstones from even the best spring wheat, they have not 
been able to get from soft winter wheat as good results as the millstone ; 
hence the roll pairs, while building up the great flouring industries of our 
Northwest, have done little or nothing for districts that used to be the flour 
centres. This was especially the case with the saw-tooth corrugation ; but 
with the advent of the round rib it is found that winter wheat can, in 
many cases, be handled better than by millstones, and even give results 
well comparable with those from spring wheat. 

In the round dress for rolls there are fewer corrugations per inch than 
with the saw tooth. It is claimed for a round rib that it does not reduce any 




Fig. 286.— V-Tooth Roll. 

of the fibre nor break the germ ; that while the sharp cut rolls will handle 
any wheat that the round ribs will, the quality will not be so good. The 
sharp cut roll gives more bran impurity from hard wheat than from soft. 
This is on all grades of wheat. In reducing particles of pure flour or 
impure rhatter the scratch roll is the best, having shallow waved corruga- 
tions, about thirty-two to the inch. These are of great use on tailings. 

Where the grooves are " saw tooth " in outline the groove edges of the 
slow roll point up, and those of the fast down, Fig. 284. By their combined 
action the wheat is cut and broken. Fig. 286 shows the V-tooth roll. 

Stevens' Patents. — The Stevens' patent No. 225,770, March 23, 1880, 
contains as claims the combinations of rolls geared to revolve at different 
peripheral rates of speed and having the dress composed of fine parallel 
grooves laid near together, with appreciable plane surfaces between, so as to 
cross each other on the contiguous surface of the rolls ; the combination of 



NUMBER AND TWIST OF CORRUGATIONS, ETC. 395 

rolls geared to revolve at different rates of speed and having the dress 
composed of fine parallel grooves laid near together and run in the same 
direction upon each roll. 

The Stevens patent No. 228,001, May 25, 1880, refers to forming the 
rolls with parallel grooves having rounded dividing ridges trending length- 
wise of the rolls ; laying the ribs in such a direction upon each roll that 
they cross each other upon the contiguous surfaces ; and when employed 
in the process of reducing grain to flour, a series of sets of such rolls, graded 
in respect to fineness or number of grooves to the inch, with intermediate 
bolts, the several sets acting in succession of grade. 

The Stevens rolls are made by John T. Noye & Sons, Buffalo, N. Y. 

Number of Corrugations.— The finer the grinding required, the 
greater the number of corrugations needed for a given diameter of roll. 
With the Stevens round rib roll, on hard spring wheat, the five breaks have 
respectively 10, 12, 14, 16 and 20 grooves per inch, and the middlings rolls 
32. For soft winter wheat sometimes there are six breaks, in which case 
the corrugations per inch on the break rolls are respectively 8, 10, 12, 14, 16 
and 20, the middlings rolls having 32, as with middlings from hard spring 
wheat. The bran rolls have 24 grooves per inch. 

T"wist of Corrugations. — The advantage of giving spiral twist to the 
flutes is to prevent the grooves of one roll from catching those of another, and 
to more effectually twist apart or break the berry. The amount of spiral or 
twist given the grooves in the Stevens rolls should vary with the character of 
the material being broken. Soft wheat takes more twist than hard, because 
it is more sticky, and more twist gives more shearing action, which frees the 
corrugations from the sticky matter. 

On spring wheat, with the Stevens system, on all breaks except the last 
one, there is only enough twist to the currugations to prevent locking to- 
gether when in motion. On the last break for cleaning bran they have a 
twist of about five inches in thirty. On winter wheat, all breaks have from 
five to six inches twist in thirty inches length. The Stevens round rib rolls 
have one inch twist for the breaks, four to six inches on the bran-rolls, and 
one inch for middlings. 

Feed and Pressure.^ — The drawing in of the grain or any other ma- 
terial between the rolls is by reason of the friction between the surface of 
the rolls and the material to be acted upon. Where the rolls are equally 
speeded, there is very little slip between the material and the roll surfaces. 

Where one roll is directly driven and the other is driven by friction 
through the chop, the speed of rotation of the other roll will be in propor- 
tion to the pressure, and will depend upon the material being ground, and 
the material and surface of the rolls themselves. In this case, of course, 
there will be rubbing upon the chop. Where both rolls are driven toward 
each other at different velocities, the speed of the feed will depend upon the 
speed of the fast roll ; but there will be some friction between the rolls and 
the particles of the chop. The greater the difference in speed the greater 
the slipping of the chop upon the roll surface. 

The greater the diameter of the rolls, the greater the friction between 

26 



396 DETAILS OF ROLLERS AND FRAMES. 

them and the material to be worked, the easier the feed, and the greater the 
capacity of rolls of a given length, speed, and material. 

The material of the rolls has a greater influence upon the work than the 
speed has. 

Axial Pressure. — The pressure upon the axes of roller mills is caused 
by two things : the weight of the rolls themselves, which is unimportant, and 
the sidewise pressure upon them exerted by the material being worked. 
All rolls should have an arrangement by which the minimum distance of 
approach of the rolls should be regulated, and the rolls should be held to 
this minimum distance by springs or weights, so that the passage of any hard 
body, as a nail, will not injure the rolls, which will spring apart and let the 
foreign substance through. 

In order that they may be thrown apart at will, with the certainty that the 
distance will be the same when they are thrown together again, there should 
be an index device to each regulating screw, so that it may set in exactly the 
same position. 

Attention should be paid to the pressure of every roller mill. For 
breaking or reducing middlings, excessive pressure would not have material 
consequence, because it is counter-balanced by set screws. But in grinding 
fine middlings, no greater amount of pressure should be applied than is abso- 
lutely necessary, because great wearing of the bearing ensues, and a large 
amount of power is consumed. 

Differential Speed. — Differential speed of rolls gives results in milling 
which cannot be obtained in any other way. In 1876 Wegmann adopted it 
for his rolls with decidedly good results. The old Pesther Walzmuehle was 
built in 1830 and arranged entirely on the 'Sulzberger system ; and it worked 
successfully and paid from year to year for a long period of time from 30 
to 50 per cent, dividends. This mill had grooved rolls for granulation, for 
regrinding the bran and for coarse middlings ; smooth rolls for reduction of 
the coarse middlings and for semolina grinding ; but Sulzberger's machine 
had three pair of rolls in each frame. Wegmann's improvements were : first, 
the use of only one pair of rolls during one crushing action ; second, of self- 
action pressure rolls, and, third, the use of a hard and gritty substance, as 
biscuit. 

At first the equally speeded rolls, worked by mere pressure and friction, 
were employed. This does well enough for reducing semolina into smaller 
particles. The differential speed adds to the capacity of the machine and 
avoids caking. 

" Professor Kick, in the new edition of his book on ' Flour Making,' states 
that, on theoretical considerations, the power consumed in crushing grain by 
direct pressure — that is, between smooth rollers without differential motion — 
is exactly double that required to reduce grain between fluted rollers with 
differential motion. This roughly coincides, says H. Simon, with the results 
obtained in practice, and carefully conducted experiments have proved that 
direct pressure, without differential speed, produces one-third less result of 
the same pressure with it. But the direct pressure without differential mo- 
tion has this further drawback, that you produce cakes instead of flour, and 



SPEED RATIOS— CAPACITY OF ROLLS, ETC. 397 

that you have to submit the product to a special process of disintegration, 
which again unnecessarily consumes power." 

• Speed Ratios. — As regards the ratios of speeds of the rolls, this differs 
with the number of corrugations and the kind of wheat to be milled. With 
hard wheat the speeds are from two and a half to five times as great on the 
fast roll as on the slow. In working soft wheat, the fast roll runs from three 
to ten times as fast as the slow. 

There is very little difference in the speed of smooth rolls. 

The " concave and single roller " mill might best be employed on mid- 
dlings. By this we mean to say, not that the concave is better for middlings 
grinding than any other means of grinding middlings, but that the concaves 
are better adapted to grinding middlings than to working any other material. 

The Stevens' rolls have for the breaks and middlings flouring, speeds of 
400 and 160 turns per minute = 5 to 2 or 2^ to i ; the bran rolls 450 and 180 
or the same ratio ; on germ, 300 and 250, or 6 to 5. 

Capacity of Round Rib Rolls. — The Stevens rolls, nine inches in 
diameter, and fifteen inches to thirty inches long, running on hard spring 
wheat, and at the speeds and with the corrugations before noted in this 
chapter, will handle from 200 to 700 lbs. of material per hour delivered to 
the "first break," and each successive set of rolls will . handle all of the 
material given it from the preceding roll. 

Details of Biscuit Rolls. — Porcelain rolls, twelve inches diameter, 
may be worked up to thirty inches in length with advantage. Above that, 
there is too much difficulty in securing equal distribution of the middlings. 
Although one pair of 30-inch rolls has not as much grinding surface as two 
pairs of 18-inch, the great expense of the frames makes it advisable to employ 
one pair of 30-inch rather than two of 18-inch. The small porcelain rolls 
are 12 inches long and 8^ inches diameter ; the large ones 17 inches long, 9 
inches diameter. The large ones make 250 revolutions per minute and the 
small ones 260. The large ones have a 6-inch single belt and the small ones 
a 5-inch, both having a 16-inch pulley, the revolutions being, as before stated, 
260 for the small and 250 forthe large. The capacity of the small machines 
is 220 pounds of middlings per hour, and that of the large ones 320 pounds 
per hour. Single machines have, of course, one-half the capacity of double 
ones. The horse-power estimated to run the machines at the above-named 
capacity is two for the small and three for the large. The weight of the 
small double machines is 2,000 pounds, all ready to run^ and that of the 
large double machine 3,200 pounds. 

Capacity of Biscuit Rolls. — As regards the capacity of the porcelain 
middlings rolls, two pairs of 9 x 24 inches should handle all the coarse stuff 
in a 200-barrel mill, if the wheat be hard. If it be soft it will require three 
pairs to •^o this work. 

Yield i.^ ">in Roller Milling. — At an experiment with roller mills, 
at Rouen, France, 2,400 kilogrammes* of medium quality soft wheat were 
reduced by the rolls. 

* One kilogramme = 2.2046 lbs. av. • , 



398 



DETAILS OF ROLLERS AND FRAMES. 



The following table gives the results obtained by the crushing 



No. of the 


Quantity 


Residue 




Unpurified 






Crushing. 


Crushed. 


after each 
Bolting. 


Flours. 


Middlings. 


Bran. 


Loss, &c. 


I 


Wheat, 2,400 


2,i6S 







en" 


c« C 








e c 


C " 


s 


a> 1 


2 

3 


" 2.I6S 
" 1,381 


1,381 
685 


c 1> 

2 w 

bD" 
C CI- 


S 5 

CS 


ogram 
r 7.5. 


ogram r 
f I per 












T:i 


4 


685 


307 


^ " 




::: 


5 


307 


188 


as 

CO 


5 

N-l 


00 

CO 

H 


u-> u 





The work completely shows as follows : 



Bakers' flour 


. 390 k 


ilogs 


= 16 per cent. ] 


Flour 


Middlings flour . 


■ 1,240 




50 " 


- of first 


Flour froTi finishing operations 


246 




10 " ) 


quality. 


Shorts .... 


360 




16 " 




Bran 


. 188 




VA " 




Loss 


12 




Vz " 





The bakers^ flour and the flour made in the finishing operations give, 
when mixed with middlings flour, flour of the first quality. Thus we get 
76 per cent, of the weight of the wheat in flour. One hundred kilogrammes 



of wheat in the roller mill at Hall, in t 



Flour, 


No. 00, 






" 0, 






I, 






2, 




Shorts, 


" 3. 
" 4. 
" 5, 
bran, loss, &c.. 





lie Tyrol, gave the following results : 



3^ 
20 

25 
12 
12 

5. 
2 
21 

100 



This mixture pro- 
)■ duces flour for white 
bread, 77 per cent. 



Total, 

The yield from a mill at Prague, in Bohemia, was as follows : 
Flour, No. 00, . 



o, 
I, 
2, 

3'. 

4, 

5. 
6, 

7, 



Shorts, bran, loss, &c.. 



3-9 

12.0 

12.0 

12.0 

12. 1 

12.5 

9-5 

3-5 

1.2 

21.3 



The mixture of these 
products gives a 
flour called straight 
flour, for white 
bread, 77. 5 percent. 



Total, 



100 



" The Decatur Mill of Shellabarger & Co. is to-day making a barrel of flour 
from four bushels and forty pounds of winter wheat (not the best), and mak- 
ing 90 per cent, of quite as good a patent as when making only 30 per cent. 



AMOUNT OF BREAK FLOUR— COLOR. 399 

Out of No. I wheat, the Decatur Mill makes a yield of one barrel of flour 
from four bushels and thirty-six pounds of wheat." * 

From hard wheat, one mill makes from 85 to 90 per cent, of flour, selling 
for more money in the same condition of the market than their old patent 
when making not over 35 per cent, of patent. The straight flour brings 
fifty cents more (with the market about the same) than before changing, while 
the mill is taking less wheat by eight pounds than before. 

One German miller finds that one pair of roller mills grinds as much as 
one pair of stones, and gives a yield of 2\ per cent, more flour two numbers 
higher grade. 

We doubt the equality of capacity, but can accept without hesitation the 
statements as to grade and yield. « 

The results of tests of a set of rollers and a pair of French burrs of 1,260 mm. 
(49.6 inches) diameter, fed with the same bran, shows the following after 
twenty-four hours' run : 

Stones. Rolls. 

Flour 3.2 6.5 

Fine middlings, .-. 1.9 2.7 

Coarse middlings, . 2.9 3.3 

Coarse middlings, . ' 7.3 10.6 

Fine bran, . .- 48.4 57.8 

Coarse bran 35.8 18.5 



99-5 99-4 

This shows for the stones 15.3 per cent, of flour and middlings, and for the 
rollers 23.1 per cent., that is, 7.8 per cent, more, while the grade is said to 
have been higher, and the power taken by the rolls much less. 

Amount of Break Flour.^ — Straight wheat all of one kind, from 
Dakota or Northern Minnesota, should not make over 8 per cent, of 
break flour, in five breaks by rolls. Soft Michigan winter wheat will 
give 25 to 30 per cent, in six breaks. We may say that with hard wheat 
the amount of break flour produced in all the breaks is about 12 to 15 
per cent. 

The number of rolls required to make 150 to 175 barrels of flour in 24 
hours varies from five to six of the grooved, according to the quality of the 
wheat being ground. In addition to this, there must be two or three smooth 
rolls for treating middlings and tailings from the purifiers. 

An eminent Austrian miller says that the grinding or squeezing- of mid- 
dlings in rolls and then disaggregating the cakes which are found by letting 
the roller work against a segment, is an advantage only up to a certain degree. 
The roller with strong ijressure is effective only until the semolinas are very 
finely reduced, and the particles are so very small that there is nothing more 
to squeeze. Then the stone, which many discarded too hastily, should be 
used for grinding the soft middlings as well as the bran. 

Color. — Roller milling so reduces the grain that there is little impurity, 
either of the bran or of the germ, that gets among the valuable material. 
It is extracted in the form in which it can be easily provided for. The mid- 

* Figures given by Mr. John Littlejohn. 



400 



DETAILS OF ROLLERS AND FRAMES. 



dlings and the Hour are then reduced in the pure state, and can be made in 
a much coarser manner and stronger than on the stone. 

Variations in the rate of speed of rolls does not have a great influence on 
the quahty of the flour, as in the case of burrs. 

Strength, of Roller Flour. — Those using new process flour should 
take notice that it requires a much larger quantity of water than winter wheat 
flours, that it must be thoroughly kneeded, and given ample time to rise be- 
fore being placed in the oven. At the test in Cincinnati in 1880, Washburn, 
Crosby & Co.'s "Superlative" brand yielded 163 pounds of dough per 
ICO pounds of flour, the "Parisian" 164-^ pounds and the "extra" 163-^ 
pounds. This is a yield of forty pounds of bread more per barrel than 
the best winter wheat flour averages. 

Power Required by Rolls. — Rolls consume less power than stone, 
in mills having just the same amount of preparation. One of the best modes 
of testing this is where a mill has been changed from stones to rolls, without 
changing any of the cleaning, bolting or purifying machinery. Some esti- 
mate a saving of 25 per cent, in power with rolls over stones, but doubtless 
15 per cent, would be nearer right. We may perhaps say 20 per cent, as the 
outside margin. 

In the experiments at the mill in Prague, elsewhere quoted (see Yield), 
to crush 2,400 kilogrammes in an hour required 10 to 12 sets of rolls, taking 
from 20 to 24 horse-power. To break up the rough middlings from this 
2,400 kilogrammes of wheat, took 5 or six sets, requiring 10 horse-power. To 
convert in an hour all the middlings from 2,400 kilogrammes of wheat, took 
a detacheur and 8 or 10 converting rolls, using in all 24 to 30 horse-power. 
Thus, for the reduction of 2,400 kilogrammes per hour, 23 to 28 sets of rolls 
are necessary, taking 52 to 64 horse- power. Adding for elevators and other 
machines 26 horse-power, we have 78 to 90 horse-power. To do the same 
work with millstones would take 28 run of stones, four being dressed at a 
time. For the 24 pairs of running stones, 120 horse-power would be needed. 

Labor Required with Rolls. — With the roller system there is less 
labor than with burrs, because there are no burrs to dress. Mr. Littlejohn 
gives, as the amount of labor needed for a 450-barrel roller mill : 



2 Engineers, at $2.50 per diem, . 


$5.00 


2 Firemen, " 1.50 " ... 


3.00 


2 Millers, " 2.50 " ... 


5.00 


I Head miller, . . . ■ . 


8.00 


I Common hand, ..... 


r.25 


2 Bran packers, at $1.25 per diem, 


2.50 


4 Flour packers, " 1.25 


.* . . 2.50 



14 men, 



$29.75 



Coolness of Roll Work. — In roller milling there is a cooler condition 
of the products ; and thus there is not only no danger of overheating and 
thus killing, but there is no loss by evaporation. The loss from this latter 
source in stone milling has been stated as from 3 to 5 pounds per barrel. 
We should, however, consider this as a merely fictitious loss. There is no 



ROLLS ON SOFT WHEATS, MIDDLINGS, ETC. 401 

liability to heat any product in the roller mill except the bran ; as, if the 
feed were stopped, none of the rolls would touch except the bran rolls. 
Sometimes, Avhere most of the reduction is done on one or two rolls, as is 
sometimes the case, there will be some heating of the chop. There will be 
less liability to this where there are six or seven reductions than where there 
are but five. 

Rolls on Soft Wheats. — An advocate of burrs said some time ago : 
" In cases where the harder wheats are used, such as those of Minnesota or 
Wisconsin, for instance, the system of gradual reduction should be found to 
be profitable. Millers using winter wheats, such as are grown in Illinois, 
Ohio, and Michigan and other States, will also find it to their advantage to 
grind higher, and regrind the bran by means of rollers. The entire roller 
system — that is, the complete reduction of wheat without the aid of mill- 
stones, has a future before it only on hard California wheat and hard Minne- 
sota Fife wheat." 

This statement may be true as regards cutting rolls, but round rib rolls 
are doing good work on soft wheat. 

Break Rolls for Soft Wheats. — Most winter wheat needs six 
breaks, while that from Michigan needs seven, the grooves having a twist of 
about three inches in thirty. 

Break Rolls for Mixed Wheat. — In Milwaukee some mills are 
running on mixed wheat, with rolls having the same corrugations as for hard 
wheat only, but there are six breaks instead of five. 

Rolls on Middlings. — -By the use of rolls millers are enabled to work 
up their coarse middlings and tailings from the middlings purifier into the 
very best flour. They crush the middlings so that they will pass through the 
meshes of the bolt, but flatten the bran and germs so that they will not pass 
through. The lower the grade of middlings to be ground, the more the 
results are to the advantage of rollers as compared with millstones. 

There is one material that can be handled by porcelain rolls, that cannot 
be done with stones, and that is the fine product, too fine to feed into the 
eye of a stone. 

Bran Cleaning by Rolls. — If rolls are used for no other purpose 
about a mill, they will pay upon bran, cleaning it well, and produce a good 
flour. 

The bran resulting from roller work is broader and less shiny than that 
from burrs, and on inspection it is found to be cleaner and less white. 

Bran cleaning by rollers, especially with winter wheat, is best done by 
several operations, the bran becoming lighter after each operation. In large 
mills the first set of bran rolls may be eight to ten inches in diameter with 
300 to 500 corrugations, those for the last operation having 800 to 900 
grooves for the same diameter. It is found that these fine rolls wear out 
quickly, and that a pair of burrs is a good adjunct to them. Oexle finds that the 
greater the difference between the roll speeds the better the bran is cleaned ; sO 
that while he commenced with i to 3 he now makes i to 250 and even i to 300. 
Oexle makes the grooves on the down roll finer than those on the up roll, 
and makes those on the fine roll straight and parallel with the roll axis. He 



402 



DETAILS OF ROLLERS AND FRAMES. 



claims for these a very exact feed, regular wear of the rolls, cleaner scrap- 
ing, and less pressure needed than with coarser corrugations. This last, of 
course, giving longer life to the rolls. In one patent of Oexle both the rolls 
may in about twenty minutes be made to run down ; so that they may be 




Fig. 287.— Gray's Roller Frame. 



run in one direction for more than one break and in the other for the others. 
This will allow the system to be introduced into smaller mills. 

Gray's Roller Frame. — The new two-pair middlings roller machine, 
Figs. 287, 288, built by E. P. Allis & Co., Milwaukee, Wis., has the following 
dimensions : height, 5 feet 6 inches ; width, 4 feet 9 inches ; length, 4 feet 9 



GRAY'S ROLLER FRAME. 403 

inches; driving pulley, 18x5^^ inches ; motion, 250 to 275 revolutions; ca- 
pacity, 3 to 4 barrels per hour ; power required, 3 to 4 horse (estimated). 
This same style of mill is built with 8-^x 14 inch rolls. 

The middling machines, with porcelain rolls, built by E. P. AUis & Co., 
have the followmg dimensions : height, 5^ feet ; width, 3 feet 9 inches ; 
length, 4 feet 6 inches ; diameter of driving pulley, 16 inches, by 5 inch 
face ; capacity 2 to 3 barrels per hour ; power estimated at 2 to 3 horse ; 
speed, 250 to 275. 

Belts are used by reason of their being noiseless, and permitting high 
speed without heating the bearings, thus increasing the capacity. All the 
belts are open or uncrossed (Fig. 288). The counter shaft jDassing through 
the base of the machine is hung in pivoted boxes raised or reversed by hand 

AflOWr Ofl DRIVING SW£ BACK SIOE 





FLOOR LINE 





Method of Driving Gray's Roller Frames. 



screws to tighten all the belts while the machine is in motion. There is a 
4-inch belt on the driving side, which drives the two high-speed rolls, one of 
which is outside and the other inside, and both running in the same direc- 
tion. The main driving belt passes under the pulley on the counter shaft, 
driving the same in opposite direction from the fast rolls. On the back end 
of this counter-shaft there are two pulleys of equal size driving the slow 
rolls. 

To lessen slipping, these pulleys are made as large as possible, generally 
twice the diameter of the rolls, although to get high speed they should be 
made smaller. The boxes of the inside rolls are made stationary. Those 
of the outside rolls are each supported by a stand or arm, pivoted to the side 
frame about 9 inches below the centre of the rollers. On the bolt or pivot 
which carries these arms there is an eccentric sleeve, the arm being bored 
out to fit on this sleeve. Thus the roller may be not only moved to and 
from the other roller, but either end may be raised or lowered to bring the 
rollers exactly in line and parallel, by turning the eccentric sleeve at either 
end of the roller. To tell whether the rollers are exactly in line — and abso- 
lute alignment is positively necessary — the proof plate is employed. This 



404 



DETAILS OF ROLLERS AND FRAMES. 



consists of a plate of iron trued perfectly plane upon one side, and stiffened 
by suitable ribs. If, in laying this upon the upper surface of the rollers, it 
rocks, the rolls are not in line, and it will be necessary to raise or lower one 
end of the movable roller of that pair. Alignment being secured, the rolls 
will granulate evenly throughout their entire length. To prevent the rollers 
from coming within a fixed distance, there is a strong spring back of each 



Y^ 




Fig. 289. — Hopper of Gray's Roller Frame. 

journal, through each of which there passes a bolt with check nuts. The 
springs can be set up to any distance apart by means of a hand-wheel and 
screw at each end. 

To spread the four rolls apart when stopping or when starting the mill, 
and to bring them back to their original position, there are two eccentrics 




Fig. 290. — Spreading Device and Adjustments. 



with a throw-out handle on the side of the frame. This is to prevent the 
belt from slipping by reason of stuff accumulated between the rolls, when 
the machine starts up. There is a handle upon the hopper, Fig. 289, con- 
nected to gates inside of the hopper, which are to shut off the feed at any 



GRAY'S ROLLER FRAME. 405 

minute, without touching or altering the adjustment of the feed-roll gates, 
intended for minute adjustment, and being located on the outside of the 
hopper. 

Fig. 290 shows the spreading device and the adjustments of the rolls and 
bearings. 

The following directions for using are furnished by the makers with each 
machine : 

First. Clean the rolls ; turn the check nut back on the pull-rod toward the centre 
of the machine ; make the roll just touch its mate, by means of the hand-wheel. Lay 
the proof plates, sent with the machine, on the bodies of one pair of rolls. If you can 
" rock " the plate, then the rolls are not parallel. Loosen the screw through eccentric 
a little, and turn the eccentric carefully with the wrench until the plate cannot be 
rocked. Now fasten the screw well, and the rolls are in working order. The rolls must 
be tried with the proof plate every four weeks. 

Second. Press the rolls together by means of the hand-wheel about as much as needed, 
bearing in mind that a great amount of power is lost by unnecessary pressure, and screw 
back the check-nuts against the swing-box, opening the rolls as much as desired. If, 
both ends of the roll are evenly apart, as can be ascertained by a piece of paper, tin, 
etc., then screw against the first check-nut the second one, therewith' locking the first one. 

Third. When stopping the whole mill, push or pull on the throw-out handle connect- 
ing the throw-out cranks, thereby opening both pairs of rolls, without disturbing the 
hand-wheel; this is to allow no leak from the feed-gate to lodge between the rolls when 
idle and cause the running oft' of driving belt after mill is started again. 

Fourth. To insure a positive motion, the belts on the back must be tightened ; this 
can be done while the machine is running. Loosen the set-screw in the sleeve, and 
screw down the centre by means of the socket wrench sent with the machine. The main 
belt can be tightened in the same manner. Tighten the set-screw again. 

Fifth. Keep the oil trough clean. Clean out the drip-pipe by entering the wire 
cleaner furnished, entering it in the little hole in circular molding, etc. 

Sixth. By turning rolls end for end, machine can be made left-handed in a few 
minutes. (Corrueated rolls, however, do not admit reversing.) Keep the bearings well 
lubricated, using the best oil and no tallow. Fill the cups with cotton wicking, and 
enter same in oil holes, so as to touch shafts. The self-oiling boxes of all ten bearings 
will work well and keep bearings cool, if properly cleaned and kept in order. There 
are oil drains below bearings, carrying the waste oil back to centre of box. These drains 
must be cleaned once in six to eight weeks. Take out the rolls and remove the little 
hard wood plugs on inside and outside face of box below shaft, enter a wire in drain- 
hole, drive in the plug again and put back the rolls, and the boxes will remain cool ; 
keep the leather packing between cap and bottom of boxes oil-tight, laying in paper 
packing, if required, to stop leaks. 



^@^ 



CHAPTER XXXIII. 

MIDDLINGS MACHINES. 

Middlings Machines — Middlings Milling by Burrs — Middlings Purifiers — Principle of the Purifier — 
Grading Middlings— Kinds of Middlings — Dusting Middlings— Keeping the Cloths Clean— Col- 
lecting and Grading Flour Dust— The G. T. Smith Purifier — Middlings Returns— Clothing- 
Number and Size of Purifiers — General Remarks on Purifiers — Grinding Unpurified Middlings — 
Bran Cleaning. 

Middlings Machines. — The main object of modern milling being 
the production and subsequent purification and reduction of middlings, we 
may properly consider as of special importance to those machines, which 
have for their object the handling and treatment of that material. 

We may divide them into those effecting grading, dusting, purification 
and reduction, with incidental reference in this connection to dust catchers 
and middlings reels. 

The various machines and processes for producing middlings, having 
been considered in detail, in their appropriate special chapters, we shall say 
but little on that head, other than to give a general introduction to this 
subject of middlings milling, as distinct from the other operations of flat or 
low milling, bolting, bran cleaning, etc. 

We must, however, spare time to lay special stress upon the fact that, 
the most successful modern milling is middlings milling, a term covering 
broadly, the intentional production of as large a proportion as possible 
of middlings, which are to be afterward floured, after being purified from 
the discoloring and innutritions matter formerly irremovable. 

Such an object and its attainment by any "system," "process," or 
combination thereof, constitutes modern milling. The principal methods of 
accomplishing the desired end are many and various. Shading almost im- 
perceptibly into each other, by reason of the "combination" and "com- 
promise " systems introduced more frequently, than pure and simple 
processes of any one type. 

There is, then, high burr milling, in which the middlings are produced on 
stones, at one operation; high burr milling, in which they are made in several 
breaks, by stones, each break followed by proper " scalping," or separation 
of the products. By means of cast-iron discs, middlings making may be 
effected, either at one or in several operations ; and single rolls working 
against a breast, and roll pairs working together, each may be employed to 
produce middlings, either in one pass or in several. The general result is 
the same — an output of middlings, ready to be treated independently of 
other products, as the source of the best grades of flour, all other operations 
and products being subordinate. 

The various compromises, combinations and complications which ensue 
preclude any satisfactory general treatment of the subject, and equally for- 



MIDDLINGS MILLING BY B URRS. 407 

bid a disquisition on any one of them, which shall be complete without a 
reference to the others, and even without a repetition of much matter be- 
longing equally under other heads. 

We must, then, while advising our readers to consider no one chapter of 
this work as complete, and to consult the others, especially in connection 
with the very copious index, apologize for what may seem, without such 
premise, needless repetition. 

Middlings Milling by Burrs. — In this connection the chapter on 
millstone dresses may be consulted with advantage, as well as that especially 
devoted to middlings purification. 

The following paragraphs have been contributed by Mr. J. D. Nolan : 

" In the first place, the burrs should be so arranged, dressed and run as to 
make the largest possible percentage of middlings, and they should be of as 
even a grade as possible. This is necessary, as it is too troublesome and diffi- 
cult to purify uneven middlings. Then the grinding of middlings is somewhat 
difficult also. The stones must not be too large — not over three feet ; they 
should be carefully and evenly dressed, and the furrows in the bed-stone 
should be shallow — not over one-eighth inch at the skirt. They should also be 
wide, with very little land. Middlings do not need much land, because there 
is no bran to clean, and, besides, they are much more easily pulverized than 
the wheat, having lost the protecting influence of the bran. Grain can stand 
rough handling because it has the bran to protect it, and it is the bran that 
wears and glazes the stone ; but the middlings, if roughly handled, stand an 
excellent chance of being killed before they reach the periphery of the stone 
as flour. Besides this, if middlings are ground with wheat they are apt to 
absorb whatever essential oil may escape from the berries ground with them 
under the stone. Middlings being very tender require careful handling ; 
they should be graded also, and each grade should be ground on a separate 
stone. Great care must be taken that the spindle does not get out of tram, 
that the stone is not in wind, and that both furrows and lands are smoothly 
dressed. A good, heavy stone of small diameter is considered the best, and 
to have this the stone should be backed up with scrap iron instead of burr- 
block spawls. 

" It sometimes happens that a miller who desires to bring up the grade of 
the flour from the first grinding often adds from one-fourth to one-half of 
the reground first middlings. This gives color and strength. Where no 
purifier is used, it is best to grind the middlings close, with a pretty heavy 
feed, in which case it would be well to use, half as many runs on middlings as 
on wheat. Where a purifier is used, in a seven-run mill, there should be at 
least three run on middlings, and they should be the sharpest and most even 
in texture and temper. In some cases it is necessary to run the burrs slowly 
in grinding middlings in order to grind fast, but it often happens that in 
slow grinding the middlings stop in the eye, and in this case it is necessary 
to use some means of forcing the middlings under the burrs. Many use a 
rod of wood placed inside of the eye and extending to the balance rynd. 
The rdtary motion imparted to the rod by the revolving stone is said to pre- 
vent choking. 



408 MIDDLINGS MACHINES. 

" The No. I middlings contain the best part of the berry, and from them 
the highest patent should be made. Although it may not slick up as white 
as that from the No. 2, it will dough up whiter and stronger. For No. i mid- 
dlings the rolls should not be set very close, and the reel should be medium fine, 
say one-half No. 11 and the other No. 12, except about eighteen inches of 
No. I at the tail. Wheat that will not pass through a finer cloth maybe sent 
to a purifier clothed with about equal lengths of Nos. 8, 5 and 3, with six 
inches of No. o on the tail end. This will take out the bran and some light, 
fluffy stuff that looks white but does up blue and without strength, being 
mostly cellulose. After purifying this material it may be sent to another set 
of rolls and reduced, and then bolted on a reel clothed with No. 12 or 13, 
and eighteen inches of No. i. What passes through the No. i may be 
finished upon biscuit rolls or burrs, making a fair second patent by using 
cloth a little finer than that of the next preceding reel. The No. 2 middlings 
may be crushed heavier, as they contain less germ, and are finer anyhow. 
They may be bolted on a reel clothed with equal lengths of Nos. 12, 13 and 
14, and about eighteen inches of No. i at the tail. The material coming 
through the No. i may be worked up with the material of the No. i mid- 
dlings, on porcelain rolls or on burrs. The No. 3 middlings may be treated 
about the same as the No. 2, but the reels will be about one number finer, the 
tailings being reduced for bakers' flour." 

An experienced miller says : " For middlings, the furrows should be 
large, flat, and have a very smooth feather-edge, say three-fourths furrow 
surface and one-fourth land. Furrows and lands should be as smooth as 
possible. Old stock stones not too open make the best granulation. New 
stock is inclined to make soft and flat middlings. 

" One reason why the middlings should never be run back to the eye of 
the stone in grinding wheat is that, if the burrs are dressed for granulating 
wheat, they cannot possibly grind middlings. In fact, a good miller will 
always dress his stones with a view to the particular kind of work they have 
to do. Besides this, the grains of wheat and particles of middlings are so 
different in size, that, when the stone is set at the proper height to granulate 
wheat, the middlings pass through without being properly acted upon, and 
when the stones are close enough to granulate, or rather ' reduce ' middlings 
the wheat is neither granulated nor ground, and this is almost tantamount to 
low grinding, which is not at all desirable in making middlings." 

Some millers claim that stones which are run too fast will make soft mid- 
dlings, which will be likely to be full of the germ and of a "red-dog" 
appearance. If there is too much land surface and not enough draft, the 
middlings will have the same appearance. 

The advocates of " new process" burr milling say, as against the roller 
system, that middlings require to be ground and not crushed, as crushing 
makes a dead flour which cannot be made lively, and produces a dead, un- 
palatable and unwholesome bread, and one earnest opponent of rolls (an 
interested champion of burrs, by the way), says : " An ordinary pair of mill- 
stones wiU do as much as four sets of rollers, and with less power. Rollers 
will often flatten the bran so that it will not appear in the flour, but will be 



PRINCIPLE OF MIDDLINGS PURIFIER. 409 

seen in the bread. One reason why rollers were introduced into Hungary- 
was that their millstones were inferior to the French." 

Middlings should be round, sharp and of as nearly one size as possible. 
Flour made from small shrunken wheat must be poorer than that from sound 
well-matured berries, and mixing them makes flour lower than the average 
of the two. It would be well to grade before sending to the smutter or 
brush. 

In trying to make all the middlings possible, remember that there is a 
danger that they may be made in bad shape, and of all different sizes, per- 
haps from No. 9 to No. 000, and this will give trouble, especially in a small 
mill, where there is no means of grading. Middhngs, from No. i to No. 000, 
cannot be purified in that condition, because they are liable to have particles 
of the bran sticking to them, instead of simply being mixed therewith. 
Another reason is that the germ or chit, which is of the same size and weight 
as fine middlings, is generally found with them, and cannot be taken out by , 
either air or silk. 

Middlings Purifiers. — Before purifiers employing both a sieving and 
an air separation came in there was great loss in the manufacture of high- 
grade flour, as it was impossible to clean the coarse bran, and, of course, all 
the gluten that adhered to it was lost. Then, again, when the middlings 
were reground, the bran dust could not be got out, and they bolted through 
into the flour. Then the specks and dust entered into the flour. 

It is the office of the purifier to remove all of the fine bran which is in 
the middlings before the latter are reground. 

The purifier is now necessary in either large or small mills working either 
old or new process. It is the only machine which will clean the flour from 
finely-divided particles of bran as fine as the flour itself, and from the fuzzy 
material that adheres to the wheat. Bolting will not take these out. There 
is as yet in general use nothing but a uniform, constant current of air that 
will do it, and this answers because they are much lighter than the middlings. 

There are few cases where the purifier should not be introduced. Of 
course there are such instances, and they are referred to under the head 
of grinding unpurified middlings; but the use of the purifier is nowadays 
generally considered as essential as the employment of cleaning machinery 
to scour the berries and brush out the crease dirt. 

The Principle of the Purifier. — The function of the purifier being 
to effect two separations, by size and by weight, giving three classes of pro- 
ducts, this is effected in most of the machines in this country by air currents 
which remove the lighter portions (principally composed of fine bran par- 
ticles), while sieves of special bolting silk remove, in suitable grades, the 
clean, hard, heavy middlings, allowing the germ middlings and coarse, 
heavy impurities to " tail over " for subsequent repurification, or for such 
disposition as may seem the most advantageous. 

In Europe other principles are employed, as, for instance, so-called 
"centrifugal force," combined with air currents; and in this country fric- 
tional electricity is proposed as a substitute ''ox the air currents, for the sep- 
aration by weight. 



410 MIDDLINGS PURIFIERS. 

Grading Middlings. — If it is essential that whole wheat berries shall 
be graded according to size before being " ended" between ending stones, 
and desirable that such grading should precede gradual reduction, where the 
capacity of the mill warrants it, it is equally advantageous to give a purifier, 
which has two classes of work to perform, material as uniform as is possible, 
that the sieves and air currents may be arranged for some special size and 
weight, and be given that and nothing else. 

Middlings should be graded when first-class work is desired. 

There are many cases where purifiers are given uneven middlings to work 
upon, and are then blamed for not doing good work. When middlings 
are even in size they can be better acted upon by both the screens and 
the air currents. Here is where the advantage of grading the middlings 
before purification comes in. Sometimes they are so uneven that there 
are some of them too large to go through the meshes of any part of the 
silk screen. 

Grading is desirable in almost every case. The number of grades de- 
pends upon the quantity of middlings. In some cases it is not economy lo 
grade too far. 

Where the improved American sieve purifiers are used it is not economy 
to make more than three or four grades of middlings. In the smaller mills 
two grades are sufficient. 

A good way to grade middlings is by reels, each grade being sent by itself 
to a purifier clothed with a cloth one number finer than the reel from which 
it came. 

Kinds of Middlings. — There is need of having some settled nomen- 
clature for millers' use. The various words middlings, shorts, sharps, grits, 
groats, semolina, and all the rest, are used indiscriminately, so it is hard to 
tell where one leaves off and the other begins. Why not use the word 
" middlings," and define it as meaning all the flour-producing part of the 
wheat that has not been reduced to flour-dust by passing it through any re- 
duction machine ? They may be subdivided into fine midds, or those that 
will pass through a No. lo cloth and over a No. 14 ; medium midds, or 
those that will pass through a No. 6 and over a No. 10; and coarse midds, 
or those that will pass over a No. 6 cloth and through a cloth coarser 
than a No. 6. The word fniddlings has but one meaning to the American 
miller, while shorts may mean pure, fine bran, or it may mean middlings ; the 
same with sharps. Grits, groats and semolina are imported words, and are 
used to designate certain sizes of middlings. 

As regards the terms "coarse," "medium" and "fine" middlings, Mr. 
Littlejohn defines, as his understanding of coarse middlings, those that will 
pass through from No. i to No. 3 cloth ; medium, those from 4 to 7 inclusive ; 
and fine, those that will pass through from No. 7 to No. 10 inclusive. All 
above No. 10 is flour and not middlings. Much patent flour is made on 
No. 9 cloth. Middlings that pass through No. 9 or 10 cloth need no purifi- 
cation. R. C. Brown considers all middlings that will pass through No. i 
cloth as No. I middlings, those that will go through No. 2 cloth as No. 2 
middlings, which is a very sensible suggestion. 



DUSTING MIDDLINGS. 411 

The easiest middlings to purify are round uniform middlings, thoroughly 
free from flour dust, without any reference to the grade of wheat of which 
they are made. 

Low grinding produces middlings that are more difficult to treat than 
those from high grinding. 

Most purifiers can treat coarse middlings from hard wheat and high 
grinding ; but those from soft wheat and low grinding are more difficult, as 
fine middlings are apt to be carried over into the dust-room. 

Soft returns from rolls, tailings and finished middlings are hard to 
purify. 

The most difficult middlings to handle are made from Fultz wheat (soft 
winter). 

The softer the middlings the greater the number of purifiers they require 
to bring them up to the same state of purification. 

It is common to get fine middlings that will pass through No. 9 or No. 10 
cloth, and these are generally sent to be ground without purifying. 

Middlings that will pass through a No. 9 or No. 10 cloth, or even a No. 
12, No. 13 or No. 14, can be purified as well and as economically as coarser, 
providing they are properly graded, and the cloth on the purifier and the air 
currents are adjusted to suit the work. 

Middlings that will pass through a No. 11 silk will not get into the stive- 
room if they are put into a purifier that is properly clothed and the air 
currents properly adjusted. 

The fibre in middlings is often so fine as to be made known only by 
the red shade. 

Dusting Middlings. — Before purifying, the middlings should be well 
dusted, not only to save the fine flour which might otherwise be carried 
away with the offal, but to increase the capacity of the purifier and lessen, 
as far as possible, the wear of the silk resulting from the constant use of silk- 
cleaning devices. As a matter of course, if the middlings are covered and 
intermingled with fine flouring particles, and are run in this condition on 
to the head of the purifier, if the air current be at all strong the nutritious 
dust will be carried over with the offal into the stive-room or the dust 
catcher. If, to prevent this, the air current be too light, then the fine 
flour dust will get through the silk and with it a certain proportion of that 
reddish material which it is the special object of the purifier to remove. 

For dusting, a reel may be used clothed according to judgment, the 
clothing having a definite relation to that of the purifier itself. 

Most mills lack dusting capacity for their middlings. The flour removed 
from the bran by the bran-duster is of an inferior quality, so much so that 
many millers do not care to save it because, though it is so white, it is life- 
less, and deteriorates the flour with which it is mixed. No miller would like 
any incorporated with his patent flour. Now, this same dead flour also ad- 
heres to the middlings. It is claimed that by the action of the disintegrator 
it is removed, and where the dusting reel is used it is saved. This material 
should be saved to be treated in any desired manner. If you ask a miller 
whether he wants his bran-duster flour in his patent flour he will promptly 

27 



412 MIDDLINGS PURIFIERS. 

say No. Yet that same miller will some time object at first to removing 
this dead flour. 

There are cases where the miller complains that his purifier is not work- 
ing well, when really it is his own fault for not supplying the machine with 
properly prepared material. 

The dust from the middlings purifier is one of the most annoying and 
dangerous things about a mill; and it is not only annoying and dangerous, 
but with the present system of drawing the air-supply of the purifier from 
the air within the mill, the lower surfaces of the cloth become clogged, 
necessitating the use of a brush or other cleaning device. It has been pro- 
posed to remedy this annoyance and expense by giving the purifier air from 
outside, uncontaminated with fine particles; but this would only be a partial 
remedy. 

The use of a dusting-reel is advantageous, as by this means much of 
the flour is taken out before the middlings go to the purifier, thus lessening 
the amount of flour that is blown into the dust-room. 

Thorough dusting of the middlings is absolutely necessary. Middlings 
cannot be economically purified, in fact, cannot be thoroughly purifierl, if 
there is any quantity of soft flour dust remaining when they go to the purifier. 
It may not be necessary in all cases to use a reel that is distinctively a dust- 
ing-reel ; but a thorough separation must be made of the flour from the mid- 
dlings before the latter go on to the purifier. This can only be done where 
the grinding has been well done, and a thorough system of bolting adopted. 

Keeping the ClotllS Clean. — As most purifiers are arranged, there 
is a constant source of trouble in the clogging of the silk screens from two 
causes — first, the actual wedging, in the meshes, of particles of middlings; 
and second, the covering of the under surface with fine floury dust, carried 
and held up against the cloth by means of the upward air current. If this 
air current be warm and moist, the trouble is aggravated. It is worse where 
the silk is of a poor grade than where the meshes are uniform in size and 
regular in shape, and free from fuzz and gum. 

A purifier without some means of keeping the cloth clean is simply 
worthless. If the meshes of the cloth are not kept perfectly free from dust 
rich material will run over with the tailings. 

The finer the grade of silk employed, the greater the necessity of keeping 
it open. With a coarse cloth the purification depends too much upon the 
air-drafts, and the assistance of the cloth is in a great measure lost. The 
most common device employed is an automatic traveling brush. 

The life of the cloth of a middlings purifier having a traveling brush is 
stated at one and a half to two years. Something depends upon the kind of 
material, the care with which the machines are operated, and the quality of 
the brush used. 

If the meshes of the cloth are not kept open good material will go over 
the tail and into the dust-room, and the middlings that are sifted through the 
cloth will be imperfectly purified. 

The underside of the cloth is clogged with dust that comes from the mid- 
dlings and from the air about the mill. No matter how thoroughly the mid- 



COLLECTING AND GRADING FLOUR DUST. 



413 



dlings are dusted or freed from flour, there is enough dust in the air about 
the mill to clog up the meshes. This might, perhaps, be largely obviated by- 
drawing the suction of the machine from the air without the mill. The dust 
could not be entirely overcome by drawing the air from without the mill, be- 
cause some dust will follow the middlings through the cloth, and this can- 
not be avoided, because flour dust is being constantly made by the action of 
the middlings upon themselves, that is, they are being constantly reduced 
by handling. 

Collecting and Grading Flour Dust. — Fig. 291 shows a mode of 
collecting and grading dust of flour and grain, and also the dust from the 




Fig. 291. 

middlings purifier. There is a balloon or balloons. A, for straining dust from 
currents of air drawn from a plant of milling machinery. The dust is blown 
into the balloons through the cloth-covered sides, the air escaping back into 
the mill. There is a hopper bottom to the balloon to receive the strained-off 
dust, which can be spouted off to where it is desired. Unless the machines 
on which such a balloon operates have these appliances for creating strong 
air currents there inay be one or more fan-blowers, K, combined with the bal- 
loon and connected by air-trunk, N, to the machine, and by another trunk, 
N', to the balloon. In Fig. 291 the elevator bolting chest B, crushing rollers 
C, stock-bin E, spout M, to stock-bin millstones F, conveyors G, are all sup- 
posed to yield substantially the same grade of flour dust, which is returned 
from the balloon to the conveyors G. The flour dust from the middlings 
purifier L is also supposed to be of substantially the same grade, and is there- 



414 MIDDLINGS PURIFIERS. 

fore returned to the crushing rollers C. The smut mill H and the brush 
machine J are supposed to yield the same grade of grain dust, which is 
therefore returned to a receptacle, I, connected with the balloon bearing on 
both the smutter and brush machine. The warm air from the machines 
and appliances can be returned into the mill to avoid any drafts of 
cold air. 

The dust catcher, if of proper construction, has the merit of assisting in 
keeping the mill temperature warm in winter, by reason of drawing the 
supply of air for the purifiers from within the mill, instead of from out of 
doors. This, of course, assists the bolting and saves fuel. 

It saves the expense and space of long ponderous dust spouts, gives the 
purifiers free vent, deposits the various grades of dust separately, and indi- 
cates at any lime what each purifier is blowing out. 

The G. T. Smith Purifier* (Fig. 292).— One of the most important 
combinations included in the G. T. Smith machines are those covered by 
United States patents Nos. 208,936 and 236,101, of which the elements are 
a shaker clothed with graded cloths, running from the finest at the head to 
the coarsest at the tail, and feed mechanism for supplying the middlings in 
a thin stream distributed equally across the entire width of the cloth ; a 
casing which, taking the air below the shaker, forms a trunk, carrying it 
through the entire extent of the cloth and above it and away through the 
fan outlet, a dust chamber being formed in the air passage, in which dust 
raised by the passage of the air through the middlings on the screen is de- 
posited. 

In the drawings of the patents, the dust-room is formed in the case ; but 
the claims are not limited to any special position, as this is manifestly not 
essential. 

So, also, the intensity of the air currents through different parts of the 
screw, as illustrated, and controlled by slides, which enable the miller to let 
on more or less air opposite any section of cloth ; and claims are made, cover- 
ing combinations, in which such means for regulating the current are ele- 
ments. As, however, the natural result of passing a column of air in motion 
through a screen of successively coarser cloths, sifting middlings as they run 
down the cloth, will be that the least current shall pass at the head, where 
not only the cloth is of finest mesh, but the material on the cloth is of greatest 
depth, and that the force of the air current will increase as the meshes grow 
more open, and the material is thinner and coarser. 

It is claimed to follow that, even without the valves, the material, growing 
coarser, will be subject to air currents of increasing force. Therefore, claim 
is made to this organization of the graded shaker, the fan and the case form- 
ing an air-trunk, not only to direct the air to the screen, but to control the 
outgoing air, so as to make it deposit in the chamber the dust with which it 
is laden. 

The effect of the graded cloth is to grade the middlings and deliver 
them in the hopper of different sizes. Sometimes it is desirable to keep them 
separate, sometimes to mingle them before grinding. The means for doing 

*Made by the Geo. T. Smith Middlings Purifier Co., of Jackson, Mich. 



416 MIDDLINGS PURIFIERS. 

this are i)rovide(l in a conveyor and series of slides, which are made elements 
in combination, covered by No. 236,101. 

In working purifiers, it was found that fibrous matter gathered on the 
cloth underneath that so effectually closed the meshes that in a little time 
the screen became inoperative. Brushes are used on the under side of the 
cloth (this is covered by the patent No. 164,050) to relieve the meshes from 
adhering particles. 

In order to enable the miller to know what is going on in his machines, 
provision is made for pockets to catch the escaping dust and permit its in- 
spection. This feature is covered by re-issued patent to G. T. and Aaron 
Smith, No. 6,197. 

When the machines were applied in large mills it was found inconvenient 
to treat all grades of middlings on one machine, and experience soon taught 
the necessity of grading middlings by passing them over a separate reel, and 
sending different grades to purifiers specially adapted to each grade. This 
combination is the subject of patent No. 158,992. 

The shakers, as illustrated in the patent, were placed side by side in the 
same casing ; but it is held that the use of independent machines, placed to 
receive and treat the different amounts coming from the section of the sepa- 
rator, is the mere adoption of an equivalent. 

The machines first introduced into the Washburn Mill were applied to 
the ordinary system of low grinding, in which the middlings were a mere 
residuum remaining after the larger product of flour had been taken out. It 
was soon concluded that the use of purifiers required a change in the mode 
of milling, and accordingly there was introduced what soon became known 
as "new process milling." 

Bearing on this there was a patent, No. 137,945, the claim of which briefly 
defines the peculiarities of new process milling as " manufacturing flour 
from middlings by subjecting them to successive grindings, boltings and in- 
termediate purification by currents of air." Whether this is really a new 
process, or an old'one revived by the aid of improved appliances, is a ques- 
tion that has never yet been adjudicated. While the grinding recommended 
is somewhat higher than that ordinarily practised, it is believed to be essen- 
tially different from the high-milling system of European mills, in which the 
breaks were into large fragmen.ts of grain and flour only as a final result. 

The latest improvement on this machine to facilitate putting on cloths, 
tightening them and changing them is as follows : Strips of wood, f of an 
inch by \\ inches, are placed at the lower edge, and on the inside pf 
the frame of the shaker. Three-eighth-inch bolts, having thumb-nuts, secure 
these strips to the shaker frame. The bolts are of sufficient length to allow the 
strips to be drawn half an inch away from and toward the centre of the shaker. 
Directly over these strips are other strips, i inch by \\ inches, and screwed 
fast to the shaker frame. The first-mentioned strips are also bolted to the 
last-mentioned, a slot being made in the last strip to permit the lower strip 
to be moved horizontally without removing the bolts. The lower strips are 
first moved toward the centre of the shaker, say half an inch, then the cloth is 
tacked to the lower edge, and tacked in the usual way across the end at the 



THE G. T. SMITH PURIFIER. 



417 



tail. At the head it is tacked to strips the same as it is at the sides. AVhen 
the cloth becomes loose, or rather slack by being stretched, it can be made 
taut again by simply turning up the thumb-nuts on the bolts, such action 
drawing the strips out toward the sides of the shaker. The cloth can be 
stretched endways by turning the nuts on the bolts which carry the strips 
across the head of the shaker. Cloth that is well stretched on at first will in time 
stretch about three-quarters of an inch, so that if we allow half an inch play for 
the strip on each, all the possible requirements are provided for. No matter 
how taut the cloth may be drawn when it is first put on, it will in a short time 
require to be taken up, or rather drawn tight again. The best results can 
only be obtained when the cloth is drawn tight, as with only such a condition 
will the middlings flow in a steady and uniform stream down the cloth. In 
many cases where makers have been called to adjust machines that were not 
working satisfactorily, they had found the cause of the trouble to be the cloth 
had not been drawn tight when put on, or it had become slack by stretching 
through use. When the cloth has been drawn tight, by turning the nuts on 
the bolts which hold the lower strips to the shaker, then the lower strip is 
drawn up to the upper one by turning the nuts on the bolts that pass through 
both strips. This upper strip being fast, to the side of the shaker, holds the 
lower one in a horizontal line. When it is desirable to change the cloth, the 
nuts on the cloth, the nuts on the bolts through the side of the shaker are 
removed, and the strips, with the cloth still attached, can be removed from 
the machine. »These strips can be removed from the machine and made fast 
in any convenient place, care being taken to place them just the right dis- 
tance apart, and the cloth can be tacked to them, at the same time stretching 
it ; then the strips can be taken up, and the cloth and strips rolled together 
and put back into the machine through the side and under the shaker, and 
the strips placed in position on the shaker. After tacking its ends, the 
cloth can be stretched as before described. If it becomes necessary, the 
cloth can be stretched while the machine is in operation, and in a very 
short time. 

GUARANTEED CAPACITY OF G. T. SMITH'S MIDDLINGS PURIFIER. 



No. 


Sq. Ft. Cloth. 


Run of Burrs. 


Bushels of Wheat 
per hour.* 


Price. 


oo Single. 


17 


I 


6 


$225 


2 " 


32 


2 


12 


400 


4 " 


47 


3 


16 


500 


6 " 


55 


4 


20 


600 


I Double. 


30 


2 




400 


2 " 


36 


2 




450 


3 " 


44 


3 




500 



Soft middlings require a longer shake than round sharp ones. The 
proper length of stroke for either soft or round middlings is the one 



* The column of bushels of wheat per hour is for medium grinding, neither very high nor very 
close, but as high as is economical without grinding the bran. 



418 MIDDLINGS PURIFIERS. 

that will keep the mass moving at the proper speed down the cloth and 
which agitates the middlings the least. The length of stroke is governed by 
the speed of the eccentric. For instance, an eccentric having a throw of 
five-sixteenths of an inch must have a speed of 500 revolutions, while an 
eccentric having a throw of three-eighths of an inch must have a speed 
of 450. 

The strength of the current should be so regulated as to keep the mid- 
dlings just a little elevated above the surface of the screen. It should be 
strong enough to carry off the lightest impurities and float the heavier ones 
over the tail. The middlings should never be much lifted from the screen. 
It is absolutely necessary that the current shall be of equal intensity on all 
portions of the cloth at any one place in its length, and that the middlings be 
equally distributed over the cloth, lest the air current seek the bare places 
and carry off more than impurities from those places while doing no cleaning 
in the crowded places. 

The head of the Smith machine produces the best middlings. " The best 
middlings are those that are the most thoroughly purified. The reason is, the 
vibration of the shaker carries the impurities to the top of the mass, the pure 
middlings going to the bottom next the cloth, and are sifted through the 
cloth toward the head of the shaker. As the mass passes down the sieve 
the quantity of pure middlings is constantly lessened, and the impurities 
reaching the cloth are sifted through with those that are too heavy to be 
wafted away by the air currents. It is at the point that where the heavy im- 
purities begin to sift through that the operator should cut off and return to 
the head of the machine. By cutting off and returning the heavier material 
the load at the tail is increased and the heavy impurities carried farther and 
farther down the sieve each time they are returned until they are at last 
forced over the tail, where it is desirable they should be sent. 

Middlings Returns. — Because the wheat berry is composed of dif- 
ferent kinds of material in different proportions, and because the various 
kernals which are being ground differ in texture and condition, there are in 
the meal, as it comes from the burrs, several grades of flour and several of 
bran. The white flour-producing portion next the skin, or bran containing 
more gluten than the other portions, is firmer and tougher than the starchy 
portion in the centre. By reason of this the ordinary process of grinding 
and bolting produces four different grades of material. 

The meal, after leaving the stone, is conveyed to the reel-bolt or series of 
bolts (sometimes after being passed through an intermediate cooler or hop- 
per-boy ; but this is not necessary, nor does it effect the number or quantity 
of the different grades) ; what passes through the head of the reel, clothed 
say with No. 10 cloth, forms a merchantable grade of flour without further 
manipulation, being sent directly to the packer. The next product of the 
reel-bolt, the returns, are frequently fine enough for high grade of flour, 
sometimes, indeed, passing through the No. 10 cloth, like the merchantable 
flour, but, containing a large quantity of fine bran and other specks, they 
cannot be put with the flour directly, lest they discolor it and lower its value. 
These portions cannot be reground, because they are already fine enough ; 



MIDDLINGS RETURNS. 419 

so they are taken back to the freshly ground chop, mixed with this last, and 
then rebolted with the same set of reels. This takes the specks out and 
increases the yield. 

The next product, the middlings, or mixture of fine bran, cockle specks, 
and other foreign substances, fuzzy fibrous materials, which have been sepa- 
rated from the skin of the berry, and the coarse grains of that part of the 
kernal which lies next the skin, contains so much gluten that, although the 
particles must have been acted upon longer than the starchy centre of the 
berry, they retain their angular form. After purifying them in a machine 
having a draft of air, and then regrinding and bolting, a part of the result is 
mixed with the flour taken from the head of the reel, and the rest is sold 
separately as^ low grade, because all of the middlings were ground at once, and 
all made fine in order to detach the bran, rendering the product difficult or 
almost impossible to bolt. In order to get flour from middlings, in which 
the granules are larger and more uniform in size than the flour made from 
the centre or starchy portion of the berry, and in order to have this product 
free from the fine dust-like particles produced by fine grinding, there has 
been devised by G. T. Smith a process (which he has protected to himself 
by letters patent) of purifying, grinding and bolting the middlings, and auto- 
matically returning the middlings returns to be again purified, ground and 
bolted. 

By this system, under ordinary circumstances, the wheat is ground upon 
stones dressed in the usual manner, and having say thirty-two cracks to the 
inch ; grinding high enough to make about 30 to 45 per cent, of middlings. 
The chop is bolted through an ordinary reel bolt, and the merchantable 
flour packed as a first grade. The middlings are elevated to the purifier, 
and, after purification, are re-ground upon a middlings stone with a perfectly 
true face and draft, and having clean regular sharp cracks. Instead of 
grinding all of the material at one operation to the desired grade of fineness, 
the middlings, meal or chop, are taken to the reel clothed with No. 10, having 
such capacity that it shall be constantly overloaded, so that about one-third 
of what is fed in shall tail over. This will prevent the specks passing through. 
The middlings returns are not fine enough for flour ; but a small proportion 
of flour will carry the specks over the tail. These middlings returns are 
taken to the purifier, the head of which is clothed with No. 10. This is in- 
tended to let the finer flour fall through, but to take out the specks and fine 
bran. 

The purified flour is put with that from the reel-bolt, or else mixed with 
the middlings meal before this is sent to the reel. The tail end of the mid- 
dlings purifier is clothed with a coarser cloth to let the larger granules of re- 
turns fall through. That which falls through being free from specks, is sent 
to the middlings stone and reground with the middlings which come from 
the first-mentioned purifier. Few of the middlings returns which are taken 
from the middlings reel are as coarse as the middlings which are treated 
upon the first purifier. Hence it is not desirable to use as coarse cloth or as 
strong draft with the shaker upon which the middlings returns are purified, 
because a strong draft would draw away the finer portions ; but a coarse 



420 MIDDLINGS RETURNS. 

cloth at the tail would let the bran through, and thus prevent sending coarse 
returns to the stone direct. It is better to put No. 7 upon the tail of the re- 
turns purifier, and to send the tailings of this purifier to the first purifier, the 
tail of which should be clothed with No. 4, to prevent anything going over 
except the ofifal. 

If it is not possible to have a seconds or returns purifier, the returns are 
sent to the middlings purifier, so that the flour will be there purified and fall 
through the No. 10 at the head. 

The force of the blast should be least on the mass while it contains much 
fine middlings and flour. Hence there will be waste from excessive dust- 
room deposits. To avoid this the middlings should be thoroughly dusted. 

In early machines, either there was only a single grade of cloth on the 
shaker, or, where graded cloths were used, there was no extension of the 
trunk above the shaker, so that the fine stuff lifted by the air was wasted, 
and, by filling the air with its inflammable particles, produced liability to ex- 
plosions such as that which destroyed the Washburn Mill in Minneapolis, 
where the latter class of machines was employed. 

Those middlings that will pass through a No. 4 or over a No. 8 cloth 
require considerable cleaning, there generally being more fine bran and 
specks than in the other grades except the germ middlings. As they are 
finer than the germ or the No. i middhngs, as strong an air current cannot 
be used with them. They should first be well dusted and then run through 
three purifiers in succession, the first clothed with equal lengths of Nos. 7, 
5, 3 and I, and six inches of No. 00 at the tail. 

It must be noted that middlings will not pass through the same number 
of cloth on a purifier that they will on a reel, because the air resists their 
tendency to pass through. Thus those that pass through this machine go to 
the next. Those that tail over go to the red-dog stone or to the shorts bin. 
The next machine may have more fine cloth at the head. If the middlings 
that pass through the cloth near the head are clean, they may go to the rolls, 
and those going through the coarser cloths may be sent to the next machine, 
which may be clothed with two-thirds of No. 5 and one-third of No. o. These 
middlings should be sent with those from the other machine to the smooth 
rolls (which should be set up very close), and the material then sent to a reel 
of the fancy chest, clothed with Nos. 12 and 13. This flour should be a 
good patent, and the tailings can be worked up well with those from other 
reels having the same kind of stock, either upon biscuit (porcelain, so-called) 
rolls or between burrs. In all cases middlings should be thoroughly dusted 
before going to the purifier, to prevent the air current from carrying away 
the fine flour dust. Of course, if the middlings are gummy, which is often 
the case with fine winter wheat middlings where the grinding is done very 
close, the inner coating of the bran is pulverized with the middlings and the 
heat produced by the friction will glutenize the fine middlings so that no 
process of purification will separate the specks from the pure fine particles 
of middlings. This is apt to take place under the roller process on 
winter wheat. 

In reply to the question, What is the best way to purify germ middlings ? 



CLOTHING. 421 

it might be answered, That purifiers are better than aspirators, because, 
although they cost more, the quality of the work is much better. 

Purifiers for germ middlings should be clothed with equal lengths of Nos. 
oo, GOO and oooo, the latter at the tail. The tailings from this machine 
should be sent to the shorts bin, although they may be sent to the low-grade 
stone to be ground into red-dog. 

Those middlings that pass through the cloth should be sent to the smooth 
germ rolls ; the other middlings may be graded into about three different 
grades, and each be purified upon a separate system. The No. i should 
pass through a No. o and over a No. 4 ; the No. 2 should pass through No. 4 
and over No. 8 ; the No. 3 should pass through No. 8 and over No. 10 or 11. 
Having them thus graded gives the miller chance to use either light or heavy 
suction on the purifiers. The No. 3 middlings should pass through three 
machines in succession. The first of these machines should be clothed with 
equal lengths of Nos. 5,4, 2, o and 00 ; the' No. 5 being at the head, what 
passes over the tail of this machine should be sent to a set of tailings rolls ; 
the middlings passing through the cloth should be sent to the next purifier 
to be recleaned. This lower machine should be clothed with equal lengths 
of Nos. 4, 2, I and 00. What passes through this machine should go to 
another clothed with Nos. 4, 3, 2, i and 00. Those that pass through the 
head of this last machine should go to the smooth rolls. Those that pass 
through near the tail can be returned to the head of the first machine. By 
this means, if the feed gets low, it may be kept up and the machine be kept 
properly loaded. 

Clotlling. — The cloth on a purifier must be graded according to the 
quantity of the material which is to be operated upon and its quality. No 
general principle or rule can be laid down for the clothing of purifiers, unless 
it may be that the cloth placed at the head must be fine enough, so that very 
little of the finest material will pass through, and graded coarser toward the 
tail, so that nearly all of the middlings will pass through' the cloth, and 
nothing be left to be passed over the tail excepting the light material which 
is held up by the air currents and floated over. There is no difference in 
clothing for spring or winter wheat. In either case the quantity and condi- 
tion of the middlings are taken into consideration in making up the cloth. 
There is little if any difference in the capacity of a purifier for handling 
spring or winter wheat middlings, quantity and condition being the same. 
Spring wheat middlings are harder and sharper than those from winter 
wheat, and are, therefore, as a rule, made freer of flour and flour dust before 
they go on to the purifier. The more thoroughly the middlings are dusted 
the greater will be the capacity of the purifier. 

There is no difference in the plan of clothing for custom and merchant 
milling ; in either case the clothing will depend entirely upon the quantity; 
quality and condition of the middlings. We mean by quality of the mid- 
dlings their size and shape. If from high grinding, with the stone in proper 
condition, the middlings will be large, sharp and round ; with the stone out 
of condition, in close grinding, they will be soft and flat. By condition we 
mean whether graded, and whether free from flour or not. 



422 MIDDLINGS PURIFIERS. 

There need be no difference in clothing for old and new process milling, 
excepting in the fineness of the cloth, and that is governed, as before, by the 
quantity, quality and condition of the middlings. 

If there is any difference in middlings necessitating a difference in 
clothing the purifier, it will perhaps be found that middlings from soft winter 
wheat are the most difficult to clean, being generally more flat and requiring 
closer cloth and more air. 

If winter wheat middlings are more flat than spring, it is because imper- 
fect stones have been used in the grinding, or the grinding has been imper- 
fectly done, in which case they would require coarser cloth and less air than 
if they were sharp and round. The flat middlings are more easily lifted and 
carried to the dust-room than sharp, round ones. The head of the purifier 
should be clothed with cloth one grade finer than the reel, and the tail should 
be clothed with cloth one to three numbers coarser than the cloth on the reel. 

Some mill furnishers say that in grading purifier cloth they are guided by 
the size of the middlings, regardless of the quality, whether from winter or 
spring wheat. 

A milling paper says : " For high grinding of spring wheat the purifier 
may be clothed at the head with from No. 6 to No. oo at the tail." If the 
middlings have first been graded on a No. 6 cloth, then the clothing de- 
scribed would be proper for a machine to handle the coarse middlings, the 
finer middlings being treated on a machine separately ; but if the whole of 
the middlings are to be sent to the one machine, finer cloth should be used 
at the head, say No. lo and grade down to No. oo. 

The popular belief that spring wheat middlings purify more easily than 
winter has doubtless grown out of the fact that the same care in grinding has 
not been taken by the winter wheat millers. Of course if the middlings are 
made flatter through poor grinding of the wheat, coarser cloth is required. 

One miller makes no difference between clothing for winter or spring 
wheat middlings. The same miller uses coarser cloth for new process work, 
as the material is coarser. 

One miller thinks that for winter wheat middlings the purifier should have 
from one to two numbers coarse cloth, and lighter air supply than for spring 
and for rye middlings, less air supply and coarser cloth than for winter wheat 
middlings. He gives one number coarser cloth for custom than for merchant 
mills, and the same air supply. He thinks that several small machines are 
better than fewer large ones of the same joint capacity, because a heavy 
weight of middlings will lie " loggy " and not allow perfect permeation with 
air. 

One authority thinks that rye middlings, being soft like those from winter 
wheat, require about the same treatment. He says that clothing and air 
supply are the same under either process — that is, you must be guided by the 
size of the middlings as to fineness of cloth, and have air supply sufficient to 
carry off impurities, but no stock. He also thinks that what is good for a 
merchant mill is good for a custom mill, and says that when more than one 
hundred pounds of middlings are made per hour it is best to divide them 
into one or more grades, to be treated on machines by themselves, always 



NUMBER AND SIZE OF PURIFIERS, ETC. 423 

taking the seconds of the finer machine and breaking them again with the 
middlings next coarser. By seconds are meant the middUngs obtained toward 
the tail-end of the shaker, which are not well enough purified to be reground, 
and are returned when only one machine is used. 

In clothing purifiers for the Jones process, of course the manner of 
clothing depends upon the middlings to be handled, but, as a general rule, it 
may be stated that for the fine Nos. lo, 8, 7, 6 and 4 should be used, and 
for the others Nos. 8, 6, 4, 2 i and o. If a scalping purifier is used, it should 
have Nos. 6, 4, 2 and 00. 

Number and Size of Purifiers. — The number and size of ma- 
chines should be proportioned to the quality and quantity of work to be 
done. In remodeling old mills, reference must always be had to the room 
and space available in which to place the machines. For instance, if one 
were running a 300-barrel mill, and making two grades of middlings, the 
larger machines should be used, and fewer of them than if greater number 
of grades were made of the same quantity of middlings. 

The size of the machine should be in proportion to the work it has to 
do. The disadvantage of a machine too large can be overcome by clothing 
finer, while a machine that is too small is always too small. 

The larger the machine, the finer the cloth and the longer the middlings 
can be retained on the sieve, permitting a more gentle application of the 
air current. 

Those who prefer a large machine say that they do so because they think 
the large machine gives better chance for the light to raise on top. 

The employment of few large machines instead of more small ones of the 
same joint capacity necessitates less attention, less spouting and elevators, 
and less room. Large machines of some makes are not as good as the 
smaller sizes, as the feeding devices are poor, so that sometimes a large part 
of the cloth is bare. 

Instead of buying one large purifier for three run of stones, many millers 
think it better to get two small ones, because they can better regulate the air- 
drafts. 

One correspondent recommends small machines. It is impossible to 
handle middlings in large quantities and do good work. It is better for the 
same material to go through two or more machines, no matter how good the 
purifiers are. 

The small purifiers are not only easier to handle, but perhaps more 
durable. 

General Remarks on Purifiers. — The use of middlings burrs and 
purifiers can be made profitable in custom mills if the system of exchange 
is adopted. 

The question is sometimes asked : If roller mills are better than stone 
mills, why are there so many more purifiers needed ? The answer is, That 
more purifiers are needed because there are more middlings to liandle, not 
because there is more bran and dirt among the middlings. 

In changing from stones to rolls, the same purifiers may be employed, 
but there will be less draught needed. Sometimes, where there is a new mill 



424 MIDDLINGS PURIFIERS. 

started, there will be back pressure upon the purifier from the stive-room, 
and thus, instead of there being less air-draft needed, there will be more 
required. 

The disadvantages of the disintegrator are that the bran remains loaded 
with flour and the flour is not of good color. In order to effect this process 
the wheat must be either naturally or artificially dampened. On the other 
hand, when looking for a system to handle damp wheats or those that have 
become artificially dampened, the disintegrator lends its aid. 

Middlings should be handled as carefully as possible to avoid breaking 
them up, and for this reason there should not be too much crank move- 
ment. 

There is a great analogy between bolting middlings without purification 
and grinding wheat without cleaning. To get three grades of middlings, 
employ three numbers of cloth, as Nos. 6, 3 and i, in the order named. To 
dust middlings, pass through a reel clothed with No. 13. Each grade of 
middlings should be ground on a separate stone. To effect this, it is well 
that the purifiers should be over the stock-hoppers, each grade having a 
separate hopper. 

The perfectly even distribution of the middlings over the entire width of 
the cloth is of the highest importance, as, if there are bare or thin places, 
not only will the distribution of air be affected, but the capacity of the ma- 
chine will be lessened. 

The coarser the middlings the more air is needed. 

The more screen surface a purifier has the more perfect and the less 
wasteful its work. 

As a rule it is not best to return material to bolts for machines through 
which it has been returned, except to help along the feed, or where there is 
too much bolting surface. 

If middlings flour is made from dry wheat it will carry all over the world. 

In ordering a purifier, send a sample of the middlings to be sent to the 
machine, and say how'many bushels of wheat will be ground per hour, or 
the number of pounds of middlings made per hour, and if the cut-off will be 
returned to the machine or otherwise disposed of. 

Grinding Unpurified Middlings. — Of course there are mills 
where the introduction of the purifier has not been effected ; and even some 
where it might not be policy to put in one — as, for instance, in a new country, 
where there is no opposition mill, and no special demand for fine grades of 
flour. In such a case, the object of the miller would simply be, with the 
smallest outlay of capital and the least skilled labor, to produce from fairly 
cleaned wheat, a marketable "straight" flour. Yet it may be desirable to 
flour the middlings separately. In this connection an old miller says : 

" To get the most and best flour from middlings without the purifier, they 
must be ground close and warm with a heavv feed, and with the burrs mak- 
ing 225 revolutions. This should give 24 pounds of good flour from 40 
pounds of middlings." 

Bran Cleaning. — This operation, also known as " bran dusting " and 
" bran dressing," was, in the days of low milling by burrs, effected between 



ERRA7^UM. 

Page 424.-67 an inadvertence, the chapter on Bran Cleaning has been 
run up into that on Purification. 



BRAN CLEANING. 435 

stones specially dressed and run therefor, and which after a fashion removed 
from the inner side of the already well rubbed bran flake some of the adher- 
ing glutenous flour and even fine middlings, adding to the white and valu- 
able material thus removed, a quota of pulverized reddish fibre, ground off 
from the bran flakes. The advent of high burr milling — in which the en- 
deavor to produce a large percentage of middlings free from bran flakes ren- 
dered the obtaining of clean bran impossible from the very nature of high 
burr milling — made bran dressing a more important factor than before, in the 
economy of the mill. 

As a supplement to the bran stones, which at best could not be given such 
a perfectly smooth dress and such perfect balance as the nature of the task 
really demanded — came the rotary brush cleaners, wire gauze cylinders, 
through which is forced the material removed from the flakes, by the rapidly 
revolving cylindrical brush. These machines effected a considerable saving 
over and above that by the stones. 

The use of chilled iron roll pairs with spiral corrugations and highly dif- 
ferential speed to effect bran cleaning, either as a continuance of " gradual 
reduction " or wheat breaks by rolls, or to follow any kind of milling which 
produces bran-bearing rich material, is highly satisfactory. 

A fourth class of bran-cleaning devices more distinctively employed for 
that purpose comprises machines having two or more rotating concentric 
cylindrical cages, armed with rods or pins parallel with the axis, these being 
generally arranged in inkles, those in one cage alternately with those in the 
other, and the distance between them being very slight. The bran flakes 
being continuously fed in at the eye or axial centre of the machine (which 
is kept full of material), or by friction among themselves and on the pins 
and the walls of the rotating cages, almost entirely denuded of the flour and 
middlings which may adhere to the valueless flakes ; while, if the operation 
is properly conducted, comparatively little innutritions and discoloring sub- 
stance is broken off. 

Many people have an idea that the bran is about as tough as india- 
rubber, and can be rolled off the wheat as though it were a regular peel. 
This is not the case, however. It requires careful handling, not only in the 
earlier stages of its separate existence, but down to the last moment when it 
is put into the dresser to have its adhering flour and middlings removed. 

That thorough bran dressing is desirable is no longer a question. It is to 
be regretted that some look at it rather as a way of thoroughly dressing the 
. bran^ than as a means of increasing the profitable yield. 

Lawton & Arndt's Bran Dresser. — This consists essentially of two 
cast-iron discs or heads rotating in opposite directions on a horizontal axis, 
each bearing on its inner face concentric circles of cylindrical steel pins pro- 
jecting about two and a half inches, and spaced wider on the inner circles 
than on the outer. The circles of pins in the two heads interlock alternately. 
The bran to be cleaned is fed in centrally by means of a screw conveyor 
running through the hollow shaft of one of the rotating "cages." 

The material in its passage outward is thoroughly whipped by the circles 
of pins passing in opposite directions. The journals are usually long, and the 



426 



MIDDLINGS PURIFIERS. 



bearings adjustable vertically to take up any wear of the brasses, and, also, 
laterally to put the discs in tram, so as to keep the circles perfectly con- 
centric and the pins accurately parallel. Each of the oppositely rotating 
discs having a speed of 6go rotations* per minute, the machine has a whip- 
ping action due a speed of 1200, and with only one-half the wear on the 
journals and brasses, while it is probable that the bran particles are more 
thoroughly turned over and over in their outward passage. 

Guaranteed Economy of Bran Dressers. — Millers are often 
unreasonable in demanding of manufacturers guarantees of performance or 
economy, when the conditions are not only unknown to the maker of the 
machine or the introducer of the process, but are absolutely not even get-at- 
able, or perhaps vary greatly from day to day. They consider, in the case 
of a bran-dressing machine, that the maker should guarantee the bran to 




Fig. 2g3 — Lawton & Arndt's Bran DREssER.t 

" lay up " below a certain maximum. The machine builders are naturally 
unwilling to guarantee any particular weight of bran as the product of their 
machines, for the reason that it is a poor proof of the manner in which it 
has been cleaned. Then there is a vast difference in the bran from dif- 
ferent kinds of wheat; that is, the fibrous woody portion of the bran is much 
thicker on some varieties of wheat than on others. A bran consisting of 
large unbroken pieces containing a considerable per cent, of valuable ma- 
terial may " lay up " light and bulky, and to such a test weighs very light to 
the bushel; while another sample, perfectly clean, broken up or ground 
down fine, may lay close and compact and weigh heavy. So the best test to 
put the bran to, is probably to inspect it and see if there is anything on it. 

What any bran-dressing machine can do depends upon the desire of the 
operator, as it does with a millstone. If run rapidly enough it will clean the 
bran thoroughly, but is apt to injure the result by making too much fine dirt 
or dust, while to run it at a more moderate feed results in better stock, but 
the bran will not be so well cleaned. 

* The expression, "revolutions per minute," might as well be corrected here as anywhere else. 
" Rotations" is the correct word for spinning on an axis— The earth "rotates" on its axis, and " re- 
volves" around the sun. 

tMade by Lawton & Arndt, Depere, Wis. 



CHAPTER XXXIV. 

BOLTING. 

Bolting— Methods Employed— Bolting Cloths— Wire Cloths— Silk and Wire Bolting Cloths Compared 
— Mending Cloths— Cleaning Cloths— Putting on the Cloth— Sliding of the Chop — Speed of 
the Reels— Capacity of Reels— Care of the Bolts— Keeping the Cloth Clean— Reels— Bolting 
Chests— Speck Box— Improved Bolting Chest— Screw Bolt Feeder— Rules for Clothing — 
To Get out Middlings— Clothing for Single Reel — Three Reels— Six Reel Chest— Scalping — 
Dusting Reel— Custom Work — Altering Reels — Reels in the Hungarian System — Wire Clothed 
Reels— The Centrifugal Machine — Wheat Meal Purification — Rebolting — Bolting for Custom 
Mills— Hints. 

Bolting. — The objects of bolting are easily stated — grading, separation, 
and purification. Reels are used to se])arate products of one kind, but of 
various sizes, as fine and coarse middlings ; to separate one or more different 
products irrespective of their value (as middlings and flour), and to take out 
impure material, which would discolor the product, as bran from flour. As 
the term is generally applied, it means the separation of the various com- 
ponents of Graham or chop, viz., flour, middlings, and bran. 

Bran, besides darkening flour by its presence, produces fermentation, 
makes sugar and gum in the bread, and gives it a dark color. 

Methods Employed. — Bolting is generally done on slowly rotating 
hexagonal reels, slightly inclined, and covered with special silk cloth, having 
meshes of extraordinary regularity of form and size. There are used, how- 
ever, cylindrical and conical reels ; and woolen cloth and wire gauze are used 
instead of silk. In addition to this, recent practice has witnessed the intro- 
duction of rapidly turning reels provided with internal brushes ; and also, 
stationary inclined sieves, against which the chop is thrown by a rapidly ro- 
tating drum. 

Bolting ClotllS. — In the manufacture of silk bolting cloths, which has 
within the past few years received such an impetus, great care must be taken 
in the selection of- raw material and in every stage of manufacture. 

The raw material is bought in the markets of Lyons, the finest and long- 
est fibres being selected. Constant supervision must be exercised in every 
stage of the process. 

The fibre is spun and re-spun, as there must be no knots or loose fibres. 
The finished bolting cloth must be heavy and strong ; the meshes perfectly 
even in size and regular in shape. Sizing must be avoided, as this rots the 
silk and clogs the meshes. The thread must be heavy and round. 

It is evident that the more fibres there are per square inch of the fabric, 
the more the manufacture costs; but this cost is not relatively proportional 
to the number of fibres, for it costs proportionately very much more to put 
in a great number of fibres than only a few. 

The fabric will be seen under the microscope to be different from ordinary 
gauzes, in that, instead of the warp or chain going simply over and under the 

28 



428 



BOL TING. 



filling, it is twisted in every mesh, not only to give strength to the fabric, but 
to prevent the fibres of the filling from moving out of place, and hence alter- 
ing the shape and size of the meshes. 

Figure 294 shows how the fibres should be. Fig. 295 has only one half of 
the fibres in one direction twisted, while in Fig. 296 there is no twisting at all. 

The reason why very much more care must be taken in the manufacture 
of bolting cloth than the finest grades of silk for wearing apparel is, that 
while in the latter case it is the fabric which is sold, and the meshes should 
properly be invisible, in the former case it is the meshes (or holes) which are 
the object of manufacture, and the purchaser desires to buy them as fine, 
regular and even as possible. The tighter the fibres are twisted, the harder 
and rounder they will be, the less fuzz they will present, the more regular the 
interstices will be, and the longer the cloth will last. 

On what is known as "extra heavy" there is the same number of meshes 
per square inch as in the regular numbers ; but the orifices are proportionately 
smaller, by reason of the stouter fibres employed. Under the microscope the 




^\_iL 



■■PHNHHi 



Fig. 294. — Good. 




Jl II U I UL 



Fig. 295. — Imitation. 



T 



Fig. 296. — Very Poor. 



meshes should not appear oblong or hexagonal, but almost perfectly square. 
Appended is a table showing the number of meshes per square inch of vari- 
ous numbers of Dufour & Co.'s Old Anker cloth : * 

DUFOUR & CO.'S BOLTING CLOTH. 

No. of Meshes to the English Square Inch. 
No. 



No. 

0000 contains 324 



000 
00 
o 
I 
2 
3 
4 
5 
6 

7 



484 


10 


784 


II 


1444 


12 


2304 


13 


2704 


14 


3136 


15 


3600 


16 


4096 


17 


5184 


18 


6400 


19 


7056 


20 



9 contains S836 

1 1 236 

I2gg6 

15376 

' 16900 

19321 

' 21904 

24336 

' 26569 

27869 

28900 

' 29929 



Bolting silk is said to be adulterated with mohair. 

Cheap cloths are often found to be at least one number coarser than they 
purport to be. 

Some dealers take a light quality of cloth and represent it as a standard 
number of good cloth, having a better cloth, the extra numbers of whicjh 



* R. P. Charles, New York. 



BOLTING CLOTHS, ETC. 



429 



they call extra heavy, and a third brand, all numbers of which they call 
double extra heavy, when in fact they have only the standard numbers of 
three different brands of cloth, and not three qualities of the same brand. 

In comparing two brands of cloth we find sometimes that one brand will 
have more meshes than the other in the finer brands, while in the coarser 
numbers it will be the other way. 

The stone is often blamed for the fault of the bolt. 

A small quantity of gum is undoubtedly required to keep the silk fibre 
from coming in contact with the middlings. To test whether the silk cloth 
has size in it wash and rub it. 

Wire Cloths. — Wire cloth is also used for bolting, and is preferred by 
some. It is carefully woven on looms built expressly for the purpose, 
and it is graded according to the fineness of the wire used in its manufac- 
ture. A very good article of wire cloth (Fig. 297) is manufactured by the 
Brooklyn Wire Cloth Works.* 



Fig. 297. — Wire Bolting Cloth. 



Silk and Wire Bolting Cloths Compared. — The following table 
shows the comparative size of meshes of wire cloth and silk bolting cloth : 

TABLE SHOWING COMPARATIVE SIZE OF MESHES OF WIRE CLOTH 

AND SILK BOLTING CLOTH. 

No. 18 Mesh Wire Cloth equals No. 0000 Silk Bolting Cloth, 324 meshes to the inch. 

484 " 
784 " 
1.444 
2,304 
2,704 
3,136 
" 3,600 " 

" 4,096 " 

5,184 

6,400 " 
7,056 
• " 8,836 

" 11,236 " 

12 996 
15,376 
" 16,900 '■ 

19,321 

-Once in a while some peddler comes about with a 
bottle of fancy cement for mending bolting cloth, and which is in reality 
nothing but a good solution of isinglass. When we say isinglass we mean 



"22 


' " ' 


' ' 000 


• 28 




' " 00 


' 30 


,1 


' " 


" 36 




" I 


' 50 




" 2 


' 54 




3 


"60 




4 


" 64 ' 




5 


' 70 


' " about ' 


6 


' 80 




7 


' 90 


' " about ' 


8 


' 100 ' 


( ( , 1 ( t 


9 


"no ' 


' <i << I 


' " 10 


" 120 ' 


t i( ( t ( 


' " II 


" 125 


' cl .1 I 


' " 12 


" 130 




13 


" 150 


' " about ' 


14 


Mend 


ing Cloths. 


— Once m a 



* F. G. Richardson, 107 John Street, New York. 



430 BOL TING. 

that material prepared from fish sounds, and not mica used by stove makers 
and often miscalled isinglass. Isinglass court-]:)laster is neat and handy, 
and mends bolting cloths well. 

Cleaning Cloths. — In some mills we find the cloths carefully cleaned, 
and in others this operation is never performed, partly because it is not the 
habit to do so, partly because no one about the mill knows how, and perhaps 
because the cloth is not good enough to stand it. There is much talk about 
the use of a brush. Some say that it is absolutely necessary, and always will 
be so ; others say that its use is only a temporary custom, and that something 
better will turn up, or the necessity for using it will be done away with. 

Putting on the Cloth. — "As bolting silk is generally about forty 
inches wide, it would be as well to make the reel so that two widths would 
cover it. Reels for custom mills ought to be 85 to 90 inches, so that, with 
the addition of ticking or webbing, the cloth would just cover." 

Some advocate putting cloth on the inside of the ribs, cutting the cloth 
in strips just wide enough to reach from rib to rib, and having the ticking 
strong enough to hold the tacks. The cloth must be tacked on the head of 
the reel and even with the inside of the rib, and then the strips stretched 
endwise as tight as possible and tacked on. Cloth must always be evenly 
stretched, else the meshes are distorted and made to clog easier. 

As to the question whether the speed of bolting reels should be increased 
or diminished when the cloth is put upon the inside of the ribs, some think 
that it should be increased considerably ; because, if run at a low speed, the 
chop slides around in a compact mass, and no air is admitted into it. 

"The finer portions are the heaviest and fall through first, next the head. 
If there is too much bolting surface, and the flour is specked, the cloth may 
be put inside of one rib and outside of the other, so that the flour will slip 
over every other rib without being lifted. This will make the reel bolt clear." 

Sliding of the Chop.— At what angle will chop slide ? Watch one 
section of the reel through one-quarter revolution ; that is, from the flat po- 
sition to a perpendicular. At 45° to 50° chop will slide, although that is not 
steep enough for a spout. At 75° to 80° bolting cloth may be used for the 
under side of a spout, without any flour coming through ; while at 50° to 
55° all will come through that can get through. 

Speed of the Reels. — How many who read this could, without count- 
ing, say how many revolutions per minute his reels are making ? 

Fast speed of the reels is a greater disadvantage than slow, because, in- 
stead of increasing the bolting capacity and quantity, the centrifugal force 
simply prevents the material from sliding along over the surface, and it is 
carried up and around and drops. 

Some say that 300 feet per minute is the maximum speed for a point on 
the circumference of a reel. 

Capacity of Reels. — The question of how full a reel ought to be to 
do the best work is best judged by watching each reel and seeing under what 
condition of fullness it does its best work. In a water-mill the air is colder 
and damper than in a steam mill. Bolting capacity is less. Good grinding, 
that is, even grinding, permits the use of coarser bolting cloths. English 



CLOTHS AND REELS. 431 

millers generally use too little bolting surface ; Hungarians and perhaps 
Americans go to tlie other extreme. 

Care of tlie Bolts. — In many mills too little care is taken with the 
bolts. They are supposed to be infallible, and to need no more care. There 
are millers who will take all possible care of their burrs, but who will never 
think of taking the slightest precaution with their chests. 

Chests should not be allowed to stand idle and partly open in cold weather, 
nor where they can be subjected either to direct spray or to dampness. If 
the reel by any means gets damp, it may be remedied by circulation of air. 

One of the greatest nuisances about a mill is a little insect, the scientific 
name of which we will not attempt to give, for two reasons : First, we do not 
think it is important, and second, we do not know it. The main question is, 
what will prevent or destroy this nuisance .' It deposits its eggs in the inter- 
stices between ribs and silk, and in cracks of the chest, and cuts the cloth. 

Turpentine is recommended, as also are knockers. 

Keeping the Clotll Clean. — It is said that a quart of dried peas 
placed in the bolting reel will increase the capacity and keep the cloth open. 
The peas are caught by a screen, turned into the elevator, and returned 
to the reel. Knockers have been tried very often, and while they fail to clear 
the bolts properly, most of them make specky flour. The best way for a 
miller to keep his cloths clear is to buy good silk to start with. 

" How many men are there traveling about the country putting in patent 
knockers guaranteed to knock spots out of every other device made, invented 
or contrived, to knock the miller from the deep hole of poverty and hard 
work to the proud and lofty pinnacle of success and affluence ? But if I 
wanted to make specky flour I would have knockers on both ends of every 
reel." 

There are cases where the agents of patent knocking devices find a mill 
in which the bolts are making specked flour, and will apply one of the knock- 
ers, at the same time putting the stones in perfect face and balance. Of 
course, after this the flour will be clearer than before, and the agent of the 
patent knocker will claim and receive the benefit. 

Reels. — " The head of the reel, it is thought by some, should be a large 
annular disc. In building the head-piece, have a pattern from which to 
make twelve cants of three-fourth inch pine lumber. Join these truly, then 
fasten one tier on the other, breaking joints in the middle, fastening with glue 
and if-inch screws. The opening in the middle should be large enough to 
admit the reel shaft conveyor. The opening is covered by a thin circular 
lid, fitting closely around the conveyor. 

" The head of the disc should be three inches larger in diameter than the 
outside of the ribs, so that if the head be turned when put upon the reel a 
groove can be cut in the middle of the edge to admit thin lining, which would 
greatly tend to make the inner parts of the chest speck-proof. Triangular 
ribs have at the base of the triangle a tangent that would cut the cloth half 
an inch above, if stretched on the reel, or the chord of an arc of a circle 
whose radius is the line from the centre of the reel to the outside ribs. The 
angle opposite the ribs is 30°. 



432 BOL TING. 

"A reel 37-0- inches in diameter clothes to advantage, because the meal, 
making a turn on the ribs, generally passes over a portion of the cloth with- 
out any bolting operation taking effect upon that strip of the cloth, whereas 
when the angle formed by the rib is more filled up and rounded off by the 
extra width of rib and of ticking, all the surface of the cloth is used in bolt- 
ing. The tail-piece can be made of three thicknesses of cants nailed together, 
the inner circle being about two inches smaller than the outer, so as to form 
a groove for admitting lining boards. 

" One authority prefers to put the cloth on light bars or sashes, with tri- 
angular cross-bars at proper intervals, with points or ends notched back and 
put on with screws. The cloth is stretched on this bar, at the inside ends of 
the apex of the triangular cross-bar, but clear of it. The sash is screwed 
down on to the ribs of the reel, instead of the bars coming flush with their 
edges, which should be slightly rounded. The ticking is tight between the 
bar and the rib, and there is no room for vermin to lodge." 

Bolting Cliests. — Each reel should have at least two conveyors (three 
are better) and an unlimited number of cut-offs. If there be several chests, 
and the flour is to be mixed, this can be done by a conveyor running at right 
angles to those under the reels. Each reel should be so arranged as to be 
inspected its entire length and at both ends at any time by opening the doors, 
which should be double, the outside doors being close and tight, and the 
inner ones covered with muslin for ventilation. The reel shafts should be 
glued up from pieces of thoroughly seasoned wood, making them firm and 
durable, and preventing all tendency to spring. The reels of conveyors 
should be all driven from the head of the chest, and the reels should be so 
arranged at the tail that they can be raised or lowered to any desired pitch 
by simply turning the screw. Each reel should be provided with double 
partitions, or false heads, forming speck boxes, which will prevent specks 
from getting into the flour. The chop should be admitted to the reels through 
an outside feed box, and should be deposited in the reel by a short conveyor 
on the reel shaft. The conveyors should all be made to project about ten 
inches at each end of the chest, and all spouts should be placed outside. 
They should be detachable and held in place by buttons, and each be pro- 
vided with a covered hand hole, to enable the miller to make an examination 
of his stuff at any point. " Each conveyor should be arranged as to be open to 
inspection its entire length without the use of sliding doors or glass, and as 
we have said before, be provided with an unlimited number of cut-offs. All ■ 
reels and conveyors should be driven from the head of the chest by upright 
shafts, the conveyors being driven by combined spur and mitre gears. 

If possible, the shafts should run in some sort of step by which the entire 
working parts of the bolt can be stopped and started at once by simply mak- 
ing a half turn with a wrench on a spindle. All chests should be provided 
with collars supported by neat iron brackets for convenience in examining the 
upper reels. By driving everything from the head of the chest torsional 
strain upon the upper conveyor may be avoided, this last being the prolific 
source of warping. This also enables the miller to have continual and instan- 
taneous control of his chest. The ends of the chest should be detachable. 



BOLTING CHESTS— SPECK BOX. 



433 



permitting the removal of the reel entire. Spouts should be large, and have 
plenty of pitch, and be polished inside to prevent clogging. It is best that 
reel conveyors should have the same number of revolutions as the reel over 
them, so that they can be run by the same gearing. 

Ordinary patent knockers will do very well perhaps where there is very 
hot grinding and very little bolting capacity, but white flour must not be ex- 
pected. There is no use in building reels to give a sliding motion to the chop 




Fig. 298. — Improved Bolting Chest. —Richmond City Mill Works. 

in order to prevent it from falling against the cloth, and then to pay a man to 
put a machine on for the express purpose of jarring the specks through. 

Speck Box. — The speck box is intended to prevent the specking of the 
flour from fine light stuff being carried up by the reel, and dusting 
through the opening in the reel. 

To prevent dusting of flour out of the heads of reels, make an inner par- 



434 



BOLTING. 



tition across the chest, a few inches in beyond the head of the reel, about as 
high as the centre of the shaft, and having a semicircle cut out for the shaft 
to revolve in. This forms the inner side of the dusting trap or hopper, of 
which the outer boarding is the outside. Between the two are inclined end 
boards, converging nearly together at the bottom of the hopper. There is 
also trouble from dusting back into the flour of the dirt from the tailings. In 
merchant bolts sometimes part of the head and tail are cut off and returned. 




Fig. 299. — Reel-Jack. 

Improved Bolting Chest. — In Fig. 298 is given an illustration of an 
improved bolting chest for new process merchant mills. This chest may con- 
sist of any number of reels, each reel having two conveyors, with an unlim- 
ited number of cut-offs. It is constructed in strict accordance with the 
specifications in the paragraph above as to " Bolting Chests." The reel- 




FiG. 300. — Improved Drop-lift Step. 



jack, which raises or lowers the reels to any desired pitch, is shown in 
Fig. 299. 

The uprights run in an improved " drop-lift " step — an ingenious con- 
trivance by means of which the working pans of the bolt can be stopped or 
started in an instant by simply making a half turn with a wrench or span- 
ner (Fig. 300). All chests are provided with galleries supported by neat iron 
brackets for convenience in examining the upper reels. 

Among the points of superiority claimed for this chest may be mentioned : 
The compound arch brackets for supporting the upright shafts and head 



IMPROVED CHEST— SCREW BOLT FEEDER. 



435 



gudgeons of the reels ; the combination of gears by which everything can be 
driven from the head of the chest, thus preventing all torsional strain on the 
upper conveyor (a prolific cause of warping), and enabling the miller to have 
a continual and instantaneous control of his chest ; the drop-lift step in con- 
nection with the above ; the reel-jack for raising and lowering the reels ; 
double doors for complete ventilation ; detachable ends permitting the 
removal of the reel entire ; improved slides for cut-offs, and increased pitch 
of slants and spouts, which are polished, preventing all clogging ; glued-up 
reel shafts ; well-proportioned and well-finished work throughout^only the 
most thoroughly seasoned and best materials being used. 

These chests are manufactured exclusively by the Richmond City Mill 
Works, of Richmond, Indiana. 

Screw Bolt Feeder. — Figures 301 and 302 show, in front and rear 
view, a device intended to be used wherever it is desirable to feed flour, mid- 





FiG. 301. — Front View. 



Screw Bolt Feeder. 



Fig. 302. — Rear View. 



dlings or meal, with regularity, into the cooler, elevator or bolts. It is fast- 
ened to the head of the bolting chest, or in any convenient place, and 
driven by a pulley upon the shaft at C. A A are the flanges or leaves 
attached to the upright shaft, and revolve with it. B is the lever governing 
them. D is a cylindrical case made of galvanized iron, resting upon and 
fastened to the cast-iron frame. The frame is so constructed as to com- 
pletely cover the gear wheels in front, and to allow a free passage of the flour 
or meal out at the back and around the base at E, while a sweep is attached 
to the shaft to prevent any lodgment on the upper part of the base. By rais- 
ing or lowering the lever B, the feed will be increased or diminished as 
desired. This feeder will run either right or left, and should make about 
twenty-five or thirty revolutions per minute. The power required is exceed- 
ingly little, as will be readily seen, while an inch belt, or even less, is all that 
is necessary to run it. The height is twelve inches, and the diameter seven 
inches. The weight is about twenty-five pounds. 

Rules for Clotlling. — There seem to be more cast-iron rules laid down 
for millers than for any other class. There are plenty of these cast-iron rules 



436 BOLTING. 

for reel clothing, and they are quoted and followed in all confidence without 
considering conditions. We find plenty of millers and mill furnishers pre- 
scribing a certain rule of clothing without the slightest knowledge whatever 
of the finer condition which should govern delicate devices of that kind. 

The coarse cloth is put on at the head of the reel, because less bran there 
comes in contact with the cloth and there are fewer specks than at the tail. 
At the tail, the fine flour being sifted out, there is hardly anything to pass 
through but fine bran and fine shorts. 

Brown recommends putting as coarse cloths as possible on the first super- 
fine reels, getting clear flour, increasing in fineness toward the tail ; putting a 
little finer on the second superfine reels, making all return to them. He says 
that if you must bolt middlings and flour in the same chest, do it in second 
reels ; and says that middlings must be bolted separately. Middlings must 
not be dusted on too fine cloths, as the flour must be got out of them before 
going to the purifier. 

There are many who put the coarse cloth at the tail of the superfine 
reels. They are wrong, because the reel, being more heavily loaded at the 
head, fewer specks come in contact with the cloth; and as these specks get 
more numerous in proportion to the mass, the cloth should be finest at the 
tail to prevent the specks from going through. 

Brown thinks that most millers bolting winter wheat use too fine cloths, 
and cites one miller grinding Michigan wheat, who raised the price of his 
flour fifty cents per barrel by changing his cloths from No. 12 to No. 10, 
thus getting a better body for his flour. 

The wheat is naturally hard and dry, and is passed through a heater. The 
meal from the wheat stone runs into a reel covered with No. 9 cloth. The 
reel has plenty of capacity, and has three feet of No. 2 at the tail, making 
the separation of the middlings from the bran also. The product from the 
No. 9 cloth goes to a reel covered with Nos. 10 XX and 11 X. After cutting 
off the flour from this reel, the remainder goes to the next reel, which is cov- 
ered with Nos. 12 X and 13. Taking off flour from this reel also, the re- 
mainder goes back as returns, but is not returned to the meal or chop, but to 
the head of the second reel (clothed with Nos. 12 X and 13). The reason 
for this, as one familiar with bolting will see, is that returns made to a coarse 
cloth are liable to produce specks, as the material has just passed through a 
cloth two or three numbers finer than the cloth at the head of the first reel ; 
and by returning to a fine cloth, or second flour reel, the liability is lessened, 
while, furthermore, you assist in keeping the second reel loaded better, so 
that both reels do a proportionate amount of work. The material passing 
over the end of the second flour reel should go to the dusting reel with the 
middlings from the No. 2 cloth on the tail end of the scalping reel. This 
dusting reel is covered with Nos. 12 X and 13. The product of this reel is 
also returned to the second flour reel, the middlings going over the end of 
the reel to the purifiers. The bran from the scalping reel goes to the bran 
duster. The reels of this chest are 16 feet long, 30 inches in diameter, and 
have two conveyors under each reel, except the scalping reel, which has but 
one. The dusting reel has two conveyors, because the middlings have to be 



RULES FOR CLOTHING. 437 

taken to the opposite side of the bolt, whence they are discharged to the 
purifiers. The middlings, after being ground, are run to a reel covered with 
Nos. 12 X and 13 cloth. After cutting off the flour, the remainder is run to 
another reel covered with twelve feet of No. 14 cloth at the head, and three 
feet of No. 10 cloth at the tail. Flour is also taken from this reel, and re- 
turns are made to its head. The product of the No. 10 cloth is carried to 
the head of the dusting reel in the other chest, as it contains some middlings, 
and as this practice has proved successful in one mill that the writer knows 
of, it is continued. We have been told by the proprietor that of three differ- 
ent kinds of purifiers the one he is now using is the only one that will treat 
this light material without waste ; and that this fact is owing to its grading of 
the middlings, cloths and air to correspond, and its easy control and adjust- 
ability. He asserts that the purifier he is using easily pays for itself every 
thirty days by taking care of the tailings from the middlings. The reels in 
this-last chest are 16 feet long also. It will be seen that this mill, with two 
run of stone, has six reels, and by the arrangement they have the proprietor 
can make a patent or straight grade as he chooses. His flour is bolted sep- 
arately, is nicely dressed, and is each a different grade ; but if he chooses to 
make a straight grade he has a conveyor that carries to one chest, and by 
feeding it into the flour from both reels in his wheat chest and both reels in 
his middlings chest the flour is well mixed and goes to one packer, making a 
superior grade of straight flour. This mill is making 25 per cent, of patent 
flour, using winter wheat, and until the last change in purifiers was obliged 
to make five barrels of low grade flour to the hundred, owing to the inability 
to purify the tailings from the middlings ; this, together with the bran-dusted 
flour, making the five barrels. 

A three-run mill, with two run on wheat and one on middlings, arranged 
like Mr. Arndt's mill, mentioned above, will have sufficient bolting capacity 
by the addition of one more reel for dusting middlings ; clothing the reel 
with No. 12 and the other with No. 13 cloth. And another purifier, run all 
the middlings into one of the purifiers and finish up the tailings with the 
other. As the above arrangements are given in cases where the mills are 
using winter wheat, I will say that for hard spring wheat I would put Nos. 11 
X and 12 cloth on the first flour reel and No. 13 cloth on the second, for 
wheat; for middlings, Nos. 12 and 13, and for dusting I would use No. 13 
cloth. Hard spring wheat does not require so much bolting surface as win- 
ter wheat, and by drying or heating winter wheat you can get along with less 
bolting surface than without any such previous preparation of the wheat. 

Some hints may be gained from the following account of a seven-run mill 
in the Sta.te of Ohio. The burrs are all four feet in diameter, dressed with two- 
thirds furrow and one-third face, medium close, old stock, turning at a speed 
of 140 revolutions per minute. The burrs are driven by gear, with springs 
on the spindle, and grind about six bushels per hour, four run running on 
wheat, two on middlings, and one grinding "stub-tail" or "red-dog." The 
wheat-cleaning machinery is as follows, all having the capacity of fifty bushels 
per hour : First, a separator ; second, a smutter ; third, a brush, and lastly, 
a heater, through which the wheat passes before going to the stone. This 



438 BOL TING. 

mill is using red winter wheat, taking about five bushels to the barrel, and is 
making 50 per cent, patent flour. The chop from the wheat stones goes to 
bolts clothed with si.x feet of No. 10 XX cloth, and the remainder with No. 
12 X, on the first reels, and six feet of No. 13 cloth, eleven feet of No. 14, and 
three feet of No. o cloth on the second reels. Flour is taken from all the four 
reels, as there are that number of reels in this chest, and the chop is divided 
equally, the returns being made to the second reels and the middlings going 
to a half chest of two reels 16 feet long, covered with No. 12 cloth, to be 
dusted. The bran goes to a bran-duster, and the flour from the bran-duster 
and the dust from the dusting reels are run together with the " red-dog " 
flour as a low grade. The middlings, after being dusted, are divided on two 
small purifiers, the tailings being finished up on a No. 4 machine of the same 
make, and all go together to the two-run stone for grinding middlings. They 
then go to another four-reel chest, the two upper reels of which are covered 
with eight feet of No. 12 X and the balance with No. 13 cloth, and the lower 
reels covered with sixteen feet of No. 14 and four feet of No. 4 cloth. Flour 
IS taken from all four reels for the patent grade. The returns are made to 
run to the lower, or second reels ; and the tailings from the middlings are 
run to the half chest of dusting reels. The bolting capacity of this mill is 
limited, but by their arrangement they are enabled to make two grades of 
flour. The proportion of the grades is fifty barrels of the first run and five 
barrels of low grade, which, as mentioned above, is the bran-duster, dust- 
ing reel and "red-dog" flour. On the ist of January, 1877, this flour was 
selling at the following prices in New York city : Patent, S9.50 ; first run, 
$8.50, and low grade, $6.25 per barrel. Calculate the matter for yourself, 
and see whether you could make money at these figures, the price of wheat 
being Si. 25 per bushel. 

A change was made in the cloths of an Indiana mill by taking off eight 
feet of No. 12 and twelve feet of No. 14 cloth from the first reel, and sub- 
stituting No. ID XX all the way through. A No. 15 cloth, used to dust the 
middlings, was then taken off and put on in its place the Nos. 12 and 14 
taken from the first reel: so prejudiced were both the proprietor and miller 
in favor of fine cloths that they believed it impossible to obtain good results 
with the cloth substituted, but after running twenty-four hours they acknowl- 
edged that their flour had been improved in quality fully twenty-five cents 
per barrel. Their middlings were much better dusted and could be purified 
without waste, and, in short, they were more than pleased with the change. 

An experienced miller says that "in considering the question of cloth- 
ing the reel, account must be taken of how much is ground per hour, and 
whether a purifier be used or not. For instance, if the capacity be six to ten 
bushels per hour, with no purifier, a 24-foot reel, 36 inches diameter, might 
be clothed with two feet of No. XX 9, ten feet of No. X 10, eight feet of 
No. X 10, and the balance, No. 4, for middlings. The slide might be arranged 
so as to cut of and return within six feet of the head of the reel when neces- 
sary. If there is a purifier, and the ground middlings be rebolted on the 
same reel, the reel may be clothed with twelve feet of No. X 11, eight feet 
of No. X 12, and the balance. No. 4 cloth, at least one-third of the feed 



TO GET OUT MIDDLINGS. 439 

entering the head being returned ; and if there be not enough capacity, more 
reels and cloths should be got." The same miller states that if the speed of 
a reel is increased by say ten revolutions, and the same amount of work re- 
quired of it, a coarser cloth will be required, because the sliding motion of 
the material in the reel is, to a certain extent, destroyed, and a revolving 
motion given instead, which of course decreases the capacity. Now, if the 
pitch be increased say one-fourth inch to the foot, a coarser cloth will also 
have to be used, providing the same amount of work is required, because 
the material acted upon will be carried along with greater velocity. 

If possible, each chest should be clothed to suit that run of stone which 
supplies it. 

To Get Out Middlings. — In order to get out middhngs, clothe the 
head of the reel with fine or flour cloth, next coarse cloth, and between the 
latter and the feed middlings cloth at the tail end, silk coarser than the flour 
cloth and finer than the second strip. Say thirty inches in a lo-foot bolt, 
No. 15 at head, then thirty-six inches No. 8 ; thirty-six inches No. 9, then 
eighteen inches No. 4. The flour from the No. 15 is returned and rebolted. 
The increasing fineness of middlings cloth raises the grade and makes it uni- 
form — as the coarse particles of grain and pieces of hull cannot pierce the 
lower end. 

A corresjjondent of the Millers' Journal asked how to clothe a 36-inch 
20-foot custom reel to bolt the product of one pair of burrs. To this the 
reply was : " There are so many methods in use, and so many different opin- 
ions among millers as to the best, that it is difficult to answer your questions in 
a manner which will satisfy all. We will say, however, that the practice which 
has given very good results is to cover your reel with No. 10 cloth. Many 
millers use four to six feet of No. 9 at the head of the reel, and the balance 
No. 10 or II, except ten or twelve inches of coarse cloth, No. 2 or 3, at the 
tail of the bolt to take out the shorts. This is for custom work. You have 
quite enough of bolting capacity in the size of the reel you mention for one 
run of burrs, grinding eight or nine bushels of wheat per hour. Some 
millers, however, would use a finer cloth than No. 10 or 11 — say No. 13 or 
14. There is quite a difference, however, in cloths, and even in the same 
cloths some will become fuzzy, and others remain smooth until worn out. 
The best motion for a 36-inch reel would be about thirty-two revolutions per 
minute with half an inch fall to the foot." 

Sometimes a mill puts in a run of burrs for merchant work only, for which 
a small separate bolting chest is desired ; but the power being limited, only a 
few reels can be used, if possible only two reels, but if necessary to good 
work, three. The chest is intended to handle the product of two run of 
burrs, although generally used for but one. The following description of a 
three-reel chest will be of use to those having need of such a chest as re- 
ferred to. 

" In the three-reel arrangement they are placed one above the other. They 
are run to separate the fine from the coarse offal, the fine flour coming out 
last. There is a conveyor under each reel. The cloths become finer in the 
second, and the third has, generally. No. 12 at head, No. 4 at tail, and the mid- 



440 



BOL TING. 



dlings from this are conveyed to the purifiers. Long reels are of the old 
school, the tendency on the part of new process millers being to use i6-feet 
or even shorter reels. A 36-inch reel is too large in diameter, as cloths which 




Fig. 303. 



are generally 40 inches wide would fit a 30-inch reel much better. Many new 
process millers use what is known as a scalping reel, in which the bran and 
middlings are separated from the flour. Then the flour goes to a finer reel, 



SINGLE, THREE, AND SIX REEL CHESTS. 441 

and so on ; but this is rather a complicated system." An arrangement with two 
bolts, one above the other, to make new process flour is as follows : " The 
meal, as it comes from the burrs, should pass through the upper reel covered 
with, say, sixteen feet of No. lo cloth and four feet of No. 4, as described 
in answer to No. i. The flour from this should pass through the second 
reel, covered with sixteen feet of No. 12 cloth and four feet of No. 3 cloth. 
At the head of second reel cut-off the first and second grades of flour, and 
purify and grind the middlings that come from No. 4 cloth on both reels. Then 
run the ground middlings into the lower reel, after grinding it on a separate 
stone, or by itself on any stone. This latter plan will be found to give satis- 
faction, and by that means the upper reel can be used for custom grinding 
without interfering with the other arrangements." 

Clothing for Single Reel. — A single reel, 20 feet long by 32 inches 
diameter to bolt six to eight bushels per hour, old process, can be clothed 
with eight feet of No. 9 at the head, then ten feet of No. 10, and two feet of 
No. 4 ; speed twenty-eight revolutions per minute. 

A reel, 24 feet by 36 inches diameter, with four feet of No. 9 XXX at the 
head, fourteen feet of No. 10 XXX, three feet of No. 6 and three feet of No. 3 
will make good family flour. The pitch may be six to eight inches, and the 
speed thirty revolutions per minute. 

Three Reels. — A new process custom mill of two or three stones may 
have a bolting chest with three reels. Three are better than two, as giving 
capacity to thoroughly dust the middlings from the fancy or middlings reel. 
Grind the wheat with one run if you have only two, or with two if you have 
three, and the middlings with the balance. Send the chop to the first reel, 
bolt out the coarse middlings and bran, send the flour to the fancy reel with 
the flour from the middlings stone, and send the middlings to the purifiers 
to be purified and sent to the middlings stone. The first reel should be so 
clothed that it can be used for rye, buckwheat and so on, without using the 
others. 

Six-Reel Chest. — Figure shows the arrangement of a chest of reels 
for making a straight grade or patent flour. As shown, the height is 17 feet ; 
width, 6 feet 6 inches ; capacity, five barrels per hour ; length of reels, 13-^ 
feet between bearings ; length of bolting surface, 12 feet. About twenty-one 
and a half pounds of chop per minute enters reel No. i at this end of the 
chest. No. T is clothed with Nos. XXio and X12, one-half of each. The flour 
is discharged at this end. The return is spouted over No. 2 into conveyor 
No. 3. What goes over the tail of No. i is elevated into No. 4, clothed with 
middlings cloth, full length, the bran discharging at this end of No. 4. The 
middlings, being in No. 5, are carried to the back end and discharged into 
No. 5, clothed with No. X12 one-third of its length, and with No. 14 the rest. 
That portion of the flour which is clear enough is dropped from the conveyor 
No. 6 into conveyor No. 7, which carries to this end, and the flour is dis- 
charged into the spout with that from conveyor No. i. The rest of the 
product of reel No. 5 is dropped into conveyor No. 8, and the middlings from 
the tail end of No. 5 dropped into reel No. 6, which is clothed with Nos. 14 
and 15X. What is dusted from the middlings on reel No. 6 is conveyed to 



442 BOLTING. 

the back end and discharged into the elevator that carries from No. i to 
reel No. 4. The reground middlings are elevated into reel No. 2, clothed 
with half chain of No. X 12-14. 

Conveyor No. 2 carries to this end and discharges its flour there into the 
spout with the flour from the conveyors Nos. i and 7, or separate as desired. 
The return from reel No. 2 is dropped from conveyor No. 2 into conveyor 
No. 3. What goes over the tail of reel No 2 is also dropped into conveyor 
No. 3, which carries to this end and discharges into reel No. 3, clothed with 
Nos. 14 and 15. The entire product of reel No. 3 is returned to reel No. 2. 
After making a straight grade the conveyor may be full the carrying way 
and one-quarter in the opposite direction, which will mix the flour. 

Scalping. — The scalper is to get the high ground meal to the proper 
consistency, so that it will bolt well in the fine reel. Although most numbers 
have been tried on the scalper, from No. 000 to No. 9, many prefer No. 7 
with a few feet of No. 00 at the tail to take out the coarser middlings from 
the bran. It has been suggested that the numbers on the scalpers be so 
arranged that middlings can be graded on it. 

Many millers contend that better bolting can be done with all of the bran 
in the chop, as all of the bolting will be done freer. With hard winter wheat 
there is very little doubt that the scalper is an advantage. 

In the matter of taking out the bran first, it is considered by some to be 
best to do this if the wheat be the soft winter variety and there be no heater. 
But where there is a heater, the bran can be taken out to advantage. 

Brown says, in the matter of scalping, that it must be done with fine 
cloths. 

For taking out the bran he recommends no coarser than No. 6 cloth, and 
no finer than No. 9. For scalping the bran from hard winter wheat chop, 
Brown recommends No. 9 cloth. 

Dusting Reel. — The dusting reel for middlings is clothed with No. 12 
or finer, and leaves the middlings sharp and distinct. After this comes grad- 
ing, or it ought to come here, because fine and coarse middlings require dif- 
ferent treatment in the purifier. Hard wheat and high grinding require 
comparatively coarse cloth, and soft grain and low grinding take finer. The 
dustings from the middlings may be run where they can best be put. 

Custom "Work. — We have been unable to see why millers will treat 
farmers, who are consumers, differently from merchants in the matter of pro- 
duct. It seems to us that to make a small mill pay, as much grist work as 
possible should be got, and the best way to get and keep this kind of trade is 
to give the farmer good flour. It is the best policy to put in a good custom 
reel and give the farmer the best grists that you can make. Run only one set 
of reels with cut-off slides to suit the grinding for one to two 4-foot burrs. 
Have the best arranged set of burrs possible, with a good long dusting bolt 
to prepare middlings for the purifier. The money that the custom reel would 
cost will buy a pony burr for grinding middlings. 

" This is not the best way, however, to economize. It would be far better 
if all of the reels were of the proper length. The dusting reel need not be 
over sixteen or eighteen feet long, and must be covered with a fine cloth, say 



ALTERING REELS— HUNGARIAN SYSTEM. 



443 



No. 14. The dusting reel should be so arranged that the middlings can pass 
directly from it to the purifier, where they are graded, and if in a small cus- 
tom mill, sent to the middlings stone, ground, rebolted, and if for a customer, 
mixed with the flour from the first reel. This plan will be found to work 
well in a small custom mill." 

Altering Reels. — " To reconstruct an old-fashioned bolting chest, take 
off all the cloths on the cant-board, move the conveyor from between the two 
reels directly under one of the reels, and put in enough conveyors to have two 
for each reel. Place all of the heads one way ; run the partition down the 
middle to the chest, and put in cant-boards for each reel. To get out the 
bran first, there will have to be a reel with one conveyor put in above the 
chest. To alter a two-reel chest, it is only necessary to put two conveyors 
under each reel and pitch both reels one way. 

Reels in the Hungarian System. — For taking out impurities, the 
arrangement shown on page 265 will answer ; or it may be somewhat varied, 
thus : 



Coarse Dirt. 



14 


14 


5 or 6 


5 or 6 



Dust, Small Seeds. 



Wheat. 



The wheat from this first reel may run to the ending machine, and then 
to the second reel thus clothed : 



14 


14 


ID 


10 



Wheat. 



Dust. 



Small Wheat. 



to take out dust and small grains. If the grain is rye, then No. 12 will be 
substituted for the No. 10 on the last two sheets. The reels under the first 
break or splitting maybe clothed with No. 14. 

The first scalping reel proper may be about seven feet long, and thus 
clothed : 



Break. 



14 


14 


14 


14 



Flour, Semolina, Middlings. 

The next scalping reel, 12 feet long, may have the first three sheets of 
No. 32 for slow-running stones, and No. 28 for quicker running mills. 



32 


32 


32 








or 


or 


or 


14 


14 


14 


28 


28 


28 









Breaks. 



Flour, Semolina and 
Fine Middlings. 



Coarse Middlings. 



29 



444 



BOL TING. 



The mixture of flour, semolina and middlings may run to the 12-foot 
reel, clothed with Nos. XL and XIII. Or, there would be used by some 
the Nos. XII., XII., XL, XL, or XII., XL, XL and X. Opinion seems to 
incline to placing the coarser numbers first, because their proportion of bran 
material holds a much larger proportion of flour. Later on, the proportion 
of bran is in the increase, tending to speck the flour even through finer cloth 
than at first give a clear product. 

In many mills the middlings is taken out by a special semolina reel, 
through which the mixture of semolina and middlings from the flouring reel 
is run : thus 



Fine Tailings. 



IX 


60 


50 


40 


28 

or 
32 



Floury 
Semolina. 



Sharp 
Semolina. 



Middlings 

No. 5. 



Middlings Middlings 
No. 4. No. 3. 



first with No. 9 silk, to let the fine floury semolina through, which latter goes 
to a dusting reel to free it from flour. The second sheet may be wire No. 
60 or silk middlings gauze No. 6, to take out the sharp semolina, the last 
three sheets being for the middlings Nos. 3, 4 and 5. The coarse middlings 
reel has upon the first two divisions Nos. XI and 60 to let through any flour, 
semolina and sharp semolina that might have remained with the coarse mid- 
dlings. The last three divisions are covered with Nos. 28, 24 and 18, the 
24 being replaced by 21 in very rapid grinding. Through this last there 
passes the middlings Nos. 3, 2 and r, bound for the middlings purifier, the 
coarse tailings passing over. 









24 




XI 


60 


28 


or 
21 


18 



Coarse Tail- 
ings. 



Floury 
Semolina. 



Sharp No. 3 No. 2 No. i 

Semolina. Middlings. Middlings. Middlings. 



As the middlings prepared for the first purification cannot be naturally 
freed from flour by the first dusting, the fine middlings — the product of the 
first purification — must be dusted upon a reel covered with Nos. X, X, 50, 
40 and 32 ; before the third purification there will be the dusting reel cov- 
ered with Nos. IX, 60, 50, 40 and 32 ; and for the coarse middlings before 
both the first purifications there will be a reel covered with Nos. IX, 60, 28, 
24 and 18. 

The semolina reel and the middlings flour, to free the semolina from light 
material, will be covered with the following numbers : 



IX 


IX 


70 

■ 


60 


54 



Floury Semolina. 



Semolina to the Purifier. 



THE CENTRIFUGAL MACHINE, ETC. 445 

Wire-Clothed Reels. — In England circular reels of brass wire cloth 
are more used than here. They generally have a revolving brush inside, 
which increases their capacity. Such reels are made in two halves, which 
can be put together over another reel of brushed, revolving slowly inside. 
Such a reel is made about six feet long and two in diameter, having arms or 
semicircles six inches apart around the inside of lengthwise ribs, which keep 
them in place, leaving the inside free for the cloth and the brushes. 

The Centrifugal Machine. — From the Millers' Journal we quote 
the following : 

" There are a great many centrifugal machines in use in England, and no 
mill is considered well equipped without one. The great complaint in a 
great many cases in numbers of our best mills is, that there is not enough of 
bolting surface and capacity, and there is a complaint of want of room to 
put up more bolts in many instances. Bolting chests take up a great deal of 
room, no doubt, and now that purifiers and scalping reels have become 
necessary articles, there is more call for space than formerly. It is a very 
difficult thing to introduce new articles of machinery from abroad, and the 
centrifugal bolt being a transatlantic machine we are slow to adopt it. The 
flour is thrown by centrifugal force against the cloth in this machine, and the 
machine is much shorter than our re.el, and travels with a very high velocity. 
Many machines of this class are only five feet long, two feet wide, and four 
feet high, and they are said to have a capacity of nearly 600 pounds per 
hour, and can be made with a much greater capacity if desired. The cloth 
wears faster than the cloth on the old style of reel ; but then that is com- 
pensated by the fact that there is much less of it used on the centrifugal, 
and its greater capacity is another thing in its favor. Besides this, the action 
of the centrifugal helps to clean the bran by disintegrating the chop. This 
is particularly the case when the milling has been done with rolls. It disin- 
tegrates the flour in such a way that any of it which might have been flattened 
by the rolls is completely pulverized, and will not pass out with the bran. 
Some say that the flour is not quite so clear as that made with the ordinary 
reel ; but if rebolting is recommended by the reel, why not by the centrifugal 
machine ? Flour made by the smooth chilled rolls is sometimes sent to the 
bolt in such large flakes that the service of a detacheur is often necessary to 
prevent great waste. It is said to act even better than a, detacheur when the 
chop is caked by the rolls, and it is claimed that it is the best device yet dis- 
covered for dusting middlings. 

" The principle of the construction of the centrifugal machine is some- 
what as follows : There is an outer and an inner cylinder. The outer one 
is covered with silk, and revolves slowly. The inner one revolves rapidly, 
making between five and six hundred revolutions per minute. This inner 
cylinder is fitted at its periphery with zinc vanes, which take up the meal and 
fling it against the silk on the outside cylinder. The vanes are fitted in a 
spiral direction from one end of the cylinder to the other, and the meal is 
therefore pushed forward at every revolution parallel to the axis. The meal 
describes a spiral line, and the middlings pass on and fall out at the end of 
the cylinder. Funnels and creepers are fitted for the outlets of the different 



446 BOLTING. 

sorts of meal or flour, so that the meal is spread over the entire surface of the 
cloth instead of being thrown only on the bottom, as in the reel, and there- 
fore a much smaller bolting surface is required to obtain the same result as 
the large bolt. 

"The separation commences on the first frame of the sieve and every 
particle comes in contact with it. The meshes of the silk never get clogged 
on account of the velocity of the inner cylinder and its great centrifugal 
force, and the meal is separated by the weight of its particles as well as by 
its size, so that the advantage of this in grading middlings is apparent. There 
are several varieties of this machine, and one characteristic is that they are 
all short, not over six feet in length. The material inside of the reel is kept 
in constant motion and agitation, and ail of the particles which may have 
only become flattened by the rollers are completely broken. The meal is 
impelled against the silk in a properly constructed machine by successive 
blows of the beaters, the heavy particles by this means maintaining their 
velocity and passing more readily through the meshes of the silk than the 
light, but the constant volley of atoms thrown against the silk and rebound- 
ing therefrom, keeping the openings practically clear, render the silk area of 
greater value than in the regular bolting reel. In order to have the reel do 
its work properly, the feed must be very regular. There must be no sudden 
slides of meal, with intervals between them, or the bolting will not be well 
done. Each revolution must determine the discharge from the reel and dress 
its own stuff. In order to keep the flour in sufficient contact with the silk, 
the beaters should revolve at such a distance from it and at such a speed that 
the flour will be thoroughly cleaned and freed from bran. The angle of the 
face of the beater should be so arranged that the particles will fly squarely 
outward to the covering and not at an angle to its surface, because if the 
particles hit the cloth at any angle the full benefit of the mesh will be lost. 

"The beaters should be susceptible to every alteration of their angles, so 
as to vary the speed of the chop through the machine. An obtuse will pass 
it quicker than an acute angle. Great care must be exercised that the re- 
volving beaters do not act as a fan, drawing a current of air through the 
feed, as this renders the machine far less effective. This can be easily un- 
derstood. When it is considered that a current of air through the silk has 
only to be strong enough to, stop up the meshes, and the more holes or meshes 
are stopped up in this way the stronger is the current through the remainder 
and the more firmly are the particles held against the orifices, and besides 
when a current of air is established it drags the light particles of gray ma- 
terial and bran through the meshes into the flour which otherwise would not 
have weight of themselves to pass. 

" Besides this, the blast is objectionable to the miller whose ideas are per- 
fect cleanliness, and to whom a puffing spout is an abomination. 

" Those millers who have made a thorough trial of the centrifugal claim 
a superiority for it over the reel. The chief points in its favor are that it 
bolts clearer, occupies a smaller space than the bolting chest, and does con- 
siderably more work, besides bolting clearer and agitating the meal better 
than the bolt. On the other hand, there are many who do not approve of 



WHEA r MEAL P URIFICA TION. 



447 



the centrifugal, on the ground that it is expensive, its construction is diffi- 
cult, and that it requires too much power to operate it, so that, like every 
other machine in milling, the centrifugal has its advocates and enemies." 

Figure 304 shows a Swiss system of " detacheur," or centrifugal bolts, 
comprising three reels, of which a receives the reduced or flattened middlings 
and lets the flour and fine middlings pass into reel b, which bolts them. 
The coarse offal and the middlings from the tail of the reel a pass into c, 
where they are bolted. 

Fig. 305 is an arrangement for low milling. There are three reels ; a and 
a receive the chop at the same time, and send the fine middlings into the reel 





Fig. 304. 



Fig. 305. 



b, which separates them ; then they are sent to other appropriate sacks. The 
flour from the reels a, a', is taken to the sacks by the spouts c c. 

Fig. 306 shows the arrangement for high milling. There are four reels, of 
which a lets fall the flour, fine middlings and offal, and sends the coarse mid- 
dlings to the cylinder b ; this one lets the flour, fine middlings, etc., through, 
and the other material tails over to the reel c. The flour and the fine mid- 
dlings are sent to the reel d, which separates them and discharges them into 
proper spouts. The reel c sorts the fine middlings, the red stuff, and the bran, 
which it sends to proper spouts. 

Wheat Meal Purification. — The object aimed at by wheat meal 
purification is to produce a pure granular flour, free from any admixture of 
the outer coatings or the abraded portions of the berry produced in the act 
of reducing the wheat to flour. The inventor claims that it being lighter in 
specific gravity than the pure flour, it readily yields to the influence of as- 



448 



BOL TING. 



cending air currents. He states that in half high milling this material exists 
in the wheat meal to the extent of lo to 15 per cent. ; he also claims that by 
removing 5 percent, of this inferior matter before bolting the chop, the flour 
first bolted is enhanced in value fifty cents per barrel, and that by removing 
10 per cent, of the same, the flour is further influenced one dollar per barrel. 
He further claims that the material removed by the gentle air currents is not 
wasted andean be bolted on an ordinary reel, when a fair, salable super flour 
is secured. If what the millers now using the process have acconiplished 
by it is correctly stated, it certainly seems very absurd for them to send 
their chop direct from the reducing mechanism to the bolts, without first 
effecting a purification of it. 





Fig. 306. 

Rebolting.^Rebolting gives good results— scalping the bran out first on 
a wire reel and then putting the flours through two or three reels with one 
cloth. If ship stuffs are too rich they must be bolted again through a very 
fine bolt. 

Bolting for Custom Mills.— One proposed arrangement of reels 
for a custom mill plans to have two 30-inch reels, sixteen feet long, 
making twenty-eight turns. The first reel has ten feet No. 6, four feet 
No. 4, and two feet No. o. The tailings go to bran bag. The product of 
the Nos. 4 and o goes to the smooth rolls, where the middlings are sized and 
the germ flattened. What passes through the No. 6 goes to the second reel, 
clothed with six feet No. 11 and ten feet No. 13. The clear flour from the 



BOLTING FOR CUSTOM MILLS. 449 

head is sacked; the returns go to the first reel, the tailings to the purifier. 
Each reel has two conveyors and plenty of cut-offs. In case of damp wheat 
the finishing reel is thrown out of gear and the flour from the No. 6 cloth 
sacked. This necessitates that the ground middlings instead of going to the 
second reel, shall be changed to the chop elevator and run to the first reel. 
The capacity of such a chest is six to eight bushels per hour. 

Another proposed bolting scheme for a custom mill gives two sixteen 
foot reels, each of two conveyors; the upper conveyor of each reel being 
the full length of the chest and the lower or return conveyors twelve feet, 
but projecting one foot beyond the head of the reel. One conveyor under 
the dusting reel the full length of the chest conveys the dustings to the 
double elevators. The outside of all the conveyor troughs is flush with the 
outside of the chest and each reel has strips on three of the ribs to drag the 
flour round and drop it into the conveyor troughs. 

Another arrangement for a custom mill is three feet of No. lo, nine feet 
of No. 12, and the rest of No. oo on the chop reel; three feet of No. ii, nine- 
feet of No. 14 and the rest of No. 4 on the middlings reel; six feet of No. 12, 
the same of No. 14 on the dusting reel. 

" Every custom mill should have a separate reel for rye and buckwheat, 
placed alongside of the wheat bolt, and run from the main shaft by a short 
shaft for the elevators, and carried to the bolt and conveyor. 

"The bearings for the bolts and conveyor should be at least four feet from 
the head of the chest, and the gear run as near as possible on the inside 
of the frame. This gives plenty of room to get to the head of the bolt." 

A four-run custom mill may be given eight elevators, six starting on the 
first floor in a line in the centre of the mill. Between the driving belts of the 
two wheat burrs comes the first elevator for wheat chop, the next elevator is 
for middlings chop, the third for corn chop, the fourth for clean wheat, the 
flftli for receiving wheat, and the sixth for receiving corn, buckwheat or 
rye ; the seventh and eighth elevators start on the grinding or second floor, 
taking the middlings from the bolts to the purifier, and from the purifier to 
the stock hoppers. 

Another recommended bolting plan for a custom mill gives two reels, the 
upper, clothed with four feet of No. 9, six feet of No. 10, six feet of No. 6, 
and two feet of No. o; the second reel has four feet of No. 10, six feet of 
No. 12, and eight feet of No. 13. The middlings are taken from No. 6 ; 
coarse middlings from No. 2, and the bran over the tail ; the rest of the 
product from the first reel going to the second, the middlings will be sent to 
the wheat meal chop and bolted with this. 

A four-reel bolting chest for a four-run custom mill is recommended as 
having 16-foot reels thirty inches in diameter running twenty-eight, the chop 
reel not having any return conveyor as the other three reels have, but set 
down as having room on top for a cooler, the top of which should be on level 
with top of reel No. 3 ; the wheat chop passes along the cooler into reel 
No. I, clothed with eight feet of No. 12 and eight feet of No. o. The flour 
from the No. 12 goes into the fourth or rebolting reel; the product of the 
No. o goes into the second reel, clothed with seven feet of No. 12, four feet 



450 BOL TING, 

of No. 4, two feet of No. 5 and three feet of No. o. The third reel, which 
is above the fourth, is covered with Nos. 14 and 16 ; what passes through 
the No. 12 on the second reel goes to No. 4 reel alongside of it, along with 
the flour from top reel No. i. The middlings passing through the Nos. 4 
and 5 on the second reel go to the purifier, the shorts going through No. o. 
The middlings chop reel No. 3 sends flour to meet the first grinding at the head 
of the fourth reel ; the tailings go as feed ; all the returns are spouted to the 
middlings chop elevator to go on to Nos. 14 and 16 cloth on the third reel. 

For a one or two run custom mill one miller recommends for the first 
boiling three reels, one above the other, on the third and fourth floors. The 
upper reel will be the scalper, and may be clothed with Nos. 6 and 2 ; the 
second one may be covered with Nos. 10 and 11. The clear flour from the 
second reel being run to the flour bin and the rest rebolted on the lower 
reel, except the returns, which should be sent to the head of the upper chop 
reel. The lower chop reel should be clothed with Nos. 11 and 12, with a 
little No. 2 at the tail ; the returns from the lower reel go to the head of the 
upper chop reel. For the middlings there is a three-reel chest, the upper 
reel being a duster clothed with Nos. 11 and 13 and receiving the product 
from the No. 2 on the scalper and on the lower chop reel. The flour from 
the middlings duster goes to the reel below it, the middlings to the purifier. 
After being floured, this middlings material joins the flour from the dusting 
reel and enters the first reel under the duster ; the clear flour from this mid- 
dle reel is drawn off, and the balance goes with its returns to the lower reel 
clothed with Nos. 13 and 14 ; the tailings from the lower chop reel and from 
the two middlings reel run to the offal of the purifier. The flours may be 
run altogether into a straight grade, or the middlings flour may be binned 
separately as a patent. 

A Wisconsin miller in Tennessee recommends for a custom mill two 
18-foot reels, the top reel having double conveyors and the lower reel 
13-foot conveyors. On the upper reel comes four feet of No. 10, ten feet of 
No. II, and four feet of No. 00. On the lower reel there is thirteen and a half 
feet of No. 12 and the rest of No. 4. The material from the No. 4 is to be sent 
to the shaker covered with No. 5, which separates the good middlings from 
the coarse, germy stuff. At the end of the short conveyor the chest should 
have a partition, and on the reel there should be a circle to keep the dirt 
specks out of the conveyor. This miller recommends attaching a spout 
eight inches square to one of the suction fans on the cleaning machine, 
drawing from the space at the tail of the chest the dust and fluff from the 
middlings as they fall from the reel into the shaker. The bran is scalped off 
at the tail of the top reel, the clear flour drawn off and the cut-off rebolted 
on the lower reel, which gets, also, the chop from the middlings burr. 

A custom mill for spring wheat and high grinding may first clean the 
bran, the chop being sent to a lo-foot scalper, the product of which will go 
to a second reel, and the bran to the bin. The scalper may be covered half 
and half, with Nos. coo and 00. The second reel may have seven feet of 
No. 9, six feet of No. 10, four feet of No. 11, and three feet of No. o. The 
flour will be taken from Nos. 9, 10 and 11, except the returns, which go back to 



BOLTING FOR CUSTOM MILLS. 451 

the head of the same reel ; what passes through No. o is sent to second puri- 
fier, clothed with Nos. 7, 5, 3, i and o; the tailings of the second reel go to an 
air purifier with the cut-off. The coarse middlings having gone through the 
purifier and the smooth rolls, go to a small shaker clothed with Nos. o and i, 
to take off the germ, fuzz, and so on. The product goes back to the head 
of the second reel, and the tailings to the finished middlings. The meal 
from the middlings stone goes to a third reel, covered with seven feet of No. 
12, six feet of No. 13, four feet of No. 14, and three feet of No. 10. Flour 
may' be drawn from the Nos. 12, 13 and 14, except the cut-off, which goes to 
the head of the second reel, with the product of the No. 10. The tailings 
from the third reel and the small shaker are run together for middlings. The 
tailings of the first reel and of the suction purifier are run together for bran. 

A somewhat elaborate bolting plan for a three-run custom mill has eight 
reels of lengths from six to twenty-three feet. Reel A is a scalper, B a 
separator, C a rebolter, D and E dusters, F for middlings, G for bran, and 
H for grading. A is clothed with four feet of No. i and two feet of dou- 
ble 00. B has seven feet of No. 9 and ten feet of No. 10. D is clothed 
with No. 16. E is twelve feet long and is covered with Nos. 16 and 18. F 
has five feet of No. 13, five of No. 14, and seven of No. 15. G has twelve 
feet No. 14 and four feet No. 4. H is only six feet long and is clothed with 
No. 4. The wheat chop from the stone goes into reel A, the bran going 
from the tail to the bran rolls, and what passes through going into B; the 
flour from B goes to C, and the middlings to D. The dust from D goes 
into E, the tail end of E goes to H, and from there to the purifiers. Flour 
from C goes to the packers as No. i ; the tail end goes to E to be dusted 
the dust being returned to the middlings chop. The flour from F enters the 
flour spout leading from C, where it is mixed and carried to the flour chest. 
The tail end of F goes in with D, being there discharged into middlings 
grader H. The bran and tailings products after going through the rolls are 
sent to G; the product of the head of G goes to E, is then returned to the 
middlings chop, and from there goes to F. The product of the tail of G is 
dusted on D, sent to H, graded as fine middlings and sent to the purifier. 

A three-run custom mill, with one run on wheat, one for middlings, and 
one on corn, may be arranged to need only five elevators ; one to take the 
chop from the wheat stone, one from the middlings stone, and one from the 
corn stone to the reel ; one which should be used for the smutter, and also, 
as a storage elevator, and the fifth, to take the wheat from the first separator 
to the brush. 

A plan recommended for an improved grist mill sends the chop from 
the burr to a 6-foot scalper, covered with No. o or 00, according to the 
wheat. The bran from the scalper goes to the bran rolls ; the inside pro- 
ducts to a two-reel flour chest — each reel having double conveyors ; the first 
reel has nine feet of No. 12 extra heavy, and the same of No. 13. The 
second reel, eight feet of No. 14, eight feet of No. 7, and two feet of No. o. 

From the first flour reel there may be drawn for flour, as much as is clear, 
the rest being sent to the product from the first eight feet of the lower, or 
separating reel, and these two being sent together as returns to the head of 
the first reels. As much of the product from the No. 7 cloth as is fit goes 



452 BOLTING. 

to the purifier, the rest to the smooth rolls with the low middlings, germs and 
seam impurities. The product from the smooth rolls to a special small bolt, 
with ten feet No. 13, and two feet No. 00 ; the bran and ship-stuff may be 
separated or thrown together as desired. The product from the head of the 
small bolt, or as much of it as is fit goes to the head of the first bolt, and the 
rest to feed, or whatever it is fit for; in grist work, it will be fit for feed only. 

Still another plan of bolting for custom work, is to send the wheat chop 
as soon as it leaves the stone to an 8-foot bran scalper, clothed with 
equal lengths of No. 2 at the head, and No. i on the tail. The bran going 
over the tail goes to the bran cleaner; the meal or chop going through the 
cloths is sent to a chest having two 18-foot reels, each having double con- 
veyors. The first reel is clothed with six feet of No. 12, six feet of No. 13, 
three feet of No. 4, and three feet of No. 3, and flour is cut off it to the end 
of No. 13; what passes through the Nos. 4 and 3 at the tail will be middlings 
and flour, and will be taken by the lower conveyors with all that you choose 
to cut off and send to the lower reel. The tailings from the upper reel will 
go to the ship-stuffs' pile. The lower reel will be covered with eight feet of 
No. 14 at the head, then six feet of No. 16, two feet of No. 9 and two feet 
of No. 8. You may cut off finished flour to the end of No. 13; the fine mid- 
dlings passing through Nos. 9 and 8 at the tail. will go to the middlings stone 
if preferred ; the tailings of the second reel will be coarse, sharp middlings, 
which should go to the purifier. The ground middlings may be bolted on 
two 16-foot reels, the upper being used as a scalper, and having only No. 
10 cloth. The tailings of this reel will be second middlings. The product 
passing through No. 10 will be taken by the conveyor below to the head of 
the second middlings reel, covered with equal parts of Nos. 12 and 14; the 
tailings of this lower reel will be very fine middlings, to be sent directly to 
the middlings stone. This lower reel may have two conveyors, with slides 
about half way; from it some finished flour may be cut off, the rest being 
taken by the lower conveyor to the second reel in the wheat flour chest, 
clothed with Nos. 14 and 15. 

Hints, — Bolting is one of the few operations that had best not be forced; 
indeed, which must not be forced. 

Every mistake or omission made to free the grain reaching the silks must 
be atoned for in dressing. 

Never depend upon the middlings to tell you how the flour is, because 
they change with the different varieties of wheat. 

There should always be a standard flour to work from, and this should 
be changed every week, so that it will not become bleached. 

It is better to have two reels than to have two cloths on one reel. 

It is very hard to try to please everybody. There are some people who 
cannot be pleased, and some who do not deserve to be pleased. It is sad to 
say, but there are several of this latter class, and several more of the former, 
among farmers. The custom miller had better stick to a good grade of flour 
made according to his own experience and judgment, and trust to have it 
appreciated by all. 

Bolts are liable to choke in feeding and must be carefully watched in 
order that the work may be regular. 



CHAPTER XXXV. 

ELEVATING, SPOUTING AND CONVEYING. 

Elevating— Link-Belt Elevators— Elevator Boot— Elevator Buckets— Air-blast Elevator— Storage Ele- 
vators — Hoppers and Sinks — Spouting— Endless-Chain Conveyors — Hollow-Shaft Conveyor — 
Pitch of Screw Conveyors— Discharge— Flexible Conveyor — Hoisting. 

The work of moving masses of material to or from one place in the mill 
from or to another, within or without, may properly be divided into ele- 
vating, spouting and cross-conveying, according to the direction of the 
material. In the ordinary processes of the mill, elevating comes first, and is 
followed by spouting and cross-conveying. 

Elevating. — In the first case, the material is raised from a lower to a 
higher level, and this is generally accomplished by an endless traveling belt 
or chain, traveling upon pulleys with parallel shafts, and having attached to 
the outer surface equidistant buckets, which pass through the lower "boot," 
fill with the material to be elevated, and in passing over the upper pulley, 
being reversed, discharge their load. As ordinarily used, the two folds of 
the bucket-bearing belt or chain travel in parallel spouts which are slightly 
inclined. 

There are two methods of carrying the buckets : (i) By flat belts, travel- 
ing on slightly craning pulleys, of which the upper one receives motion and 
is hence the driver of the two ; and (2) By malleable iron "link-belts," to 
"chain-belts" running on sprocket wheels, the lower being the driver. 

Each of these systems has its advantages and its demerits, according to 
the surroundings and circumstances. 

A very high elevator should be as nearly perpendicular as possible, else 
the cups will soon wear out. The wheat elevator need not be run as fast as 
the flour elevator, as the grain, being lighter, discharges quicker. 

The great diversity of heights and capacities of elevators render it im- 
practicable for us to give detailed information on the subject, but in making 
inquiries for specific instructions, the location, height, required capacity, and 
speed of line-shaft should be given. 

Wheat elevators should have revolving spouts, so that in case of storing 
wheat it can be run to any part of the mill. 

If the bolting chests are placed above the grinding floor, the latter set 
back, the elevator will not come in contact with the hurst, from which it 
may be separated, as mentioned elsewhere, about four feet, being run upon a 
short shaft on the second floor, connecting with the main shaft on a movable 
sleeve beveled gear. The same shaft will answer for driving an elevator 
for the coarse grain. 

The meal elevator should have a valve so that the meal may be run to a 
shake-sifter or direct to the bag, as desired. 



454 



ELEVAT/XG, SPOUTIXG AND COXVEYIXG. 



Link-Belt Elevators. — Link-belt elevators, with either single or 
double strands of chain, as circumstances may require, will, if properly 
erected and suitable chain and buckets selected, give satisfaction, and too 
much stress cannot be laid on the importance of starting correctly. We 
showed in cuts (Figs, no and 112, page 217), two styles of elevators; the 
one having a single strand of chain differs from those now in use, simply 
in having chain instead of leather or rubber belting to carry the cups. The 
double strand elevator, however, has new features that will be readily under- 
stood and fully appreciated by mill men. The suspended buckets are so 
hung that the chains support them in a line at or near their centre of gravity, 




Fig. 307. -Elevator Boot. 



thus relieving the chains of the overhanging strain present in the old forms 
of elevators. The counter wheels at the head render the discharge much 
more perfect and independent of any centrifugal action, as the buckets are 
in turn inverted directly above the shute. This feature gives the elevator a 
great latitude as to speed, and it will work satisfactorily under all the vari- 
ations of speed and material that are liable to be met with. 

The detachable link-belt and its wheels will fairly wade through grain 
and elevate, although the boot is filled, and as the supply may safely be kept 
in excess, the buckets will fill and carry and the elevator work to its full ca- 



ELEVATOR BOOT. 



455 



pacity. One of the most important advantages of the link-belt elevator 
is that it may be driven from the bottom and with very little tensional strain 
to keep it at work. The usual type of belt elevator is generally driven from 
the top, necessitating extra strength in the housing to stand the pull on the 
belt, and also requiring a main driving belt from the engine clear to the top 
of the warehouse. Where the link-belt elevator is used and driven from the 
boot, it is usual to run a line-shaft near the boot and to drive the elevator 
with a smaller chain than the one which carries the buckets, so that in case 
an obstruction occurs in the elevator, the light driving chain will break and 
the elevator buckets and chain saved from damage, just as the chain serves 
as a safety point in harvesting machines. 

Elevator Boot. — The Caldwell Patent Elevator Boot,* Figure 307, 
is adjustable, because the bottom and sides to the boot proper are fastened to 




Fig. 308. — Elevator Boot — Section. 

the shaft on which the pulley goes, so that when the pulley is raised or low- 
ered to tighten or loosen the belt, this bottom boot or receptacle goes up 
and down with the pulley independent of the outside ends, and the bottom of 
the boot remains the same distance from the bottom of the pulley under all 
circumstances ; outside of this inner receptacle are the heavy cast-iron sides 
that support the leg or trunk, which is made of wood in the ordinary manner. 
The shaft works up and down in these sides on gibbed guides governed by 
rods on each fastened to the journal-box, as shown in Fig. 307, and these 
rods are provided with suitable hand-wheels, situated at the most convenient 
point for handling, and work on the proper thread. The pulley is raised or 
lowered by turning the hand-wheels. This inner cradle or basket-shaped 



* H. W. Caldwell, Chicago, 111. 



456 ELEVATING, SPOUTING AND CONVEYING. 

boot has its edges pass up under cast-iron aprons which are securely fastened to 
the outer part or sides of boot, so that the play up and down is well provided 
for and leakage is prevented. There is also side play allowed, so that the 
pulley in the boot can be run off a level, as is often required from some 
settling of building or stretching of belt, over which there would otherwise be 
no control. The buckets scrape close to the bottom and take up all the 
material, leaving the boot clean. This is of great importance in run- 
ning one class of material after another, or different grades or kinds of grain. 
There is no mixing of grades in this boot unless two kinds are run in it at 
once. There is a slide in the bottom easily opened or closed. It cannot 
easily be choked, because the buckets occupying their proper distance apart 
on the belt, and fitting close to the bottom, will let in material only in such 
quantity as the bucket has capacity to take, and any surplus will back up in 
the feed spout ; so you can start or stop when the feed is on without closing 
the feed gate. 

There are two styles of this boot made, one called " low feed," adapted 
for large elevators, and where it becomes necessary to have the feed at a low 
point on the pulley ; the other, or "high feed," is used when the height of 




Fig. 



309. 



feed makes no difference. The parts or sections forming the boot are easily 
removed in case of accident, and are numbered so that duplicates can be 
readily obtained if desired. The point of feed is stationary in both patterns ; 
the rise and fall of the pulley is independent of the feed. 

Elevator Buckets. — It is astonishing how, in the great Hungarian 
mills, they can make a profit when there is so much money wasted in labor- 
ers' wages in carrying material from floor to floor and from place to place. 
The elevator in its present form, invented by Oliver Evans, and introduced 
by him, in 1783, together with the conveyor, into his brother's mill, is un- 
known in many European mills. 

It is estimated that the elevator, with its twin invention, the conveyor, has 
effected a saving of 50 per cent, of labor in the mill. 

The buckets attached to the endless belt have been made of wood, 
leather, paper, pig skin, " tin" and iron. " Tin" and iron ai'e most generally 
employed in this country ; the general shape being the frustrum of an ob- 
lique pyramid, the mouth being oblong and the front tapering back. Such 
shaped buckets have the disadvantage of being liable to accidents from 
catching in the elevator leg if the belt twists, and in many cases the wrench- 



ELEVATOR BUCKETS. 



457 



ing they undergo in passing through the material in the boot opens their 
seams and tears their lips, besides wrenching them from the belt. 

The most approved bucket of which we have any knowledge is the 
"Due,"* which seems to obviate both of the difficulties we have named. Its 
mouth is spherical, and the whole outline is devoid of any seams or corners, 
except where the curved front is joined to the straight back which lies 
against the belt. In consequence, the passage of such a bucket through the 
material in the boot is much easier than if it had square corners and entered 
the material suddenly. It fills more readily and is more apt to take a full 
load than the oblong bucket, and there being no interior corners to clog, it 
is more likely to deliver all that it carries up. It is shown in the illustra- 
tion, Fig. 309. This bucket is struck out by a die from cold-rolled char 
coal stamping iron, and is manufactured in two weights, viz., light and heavy. 
The buckets from the light material (No. 24 iron) are intended for use in 
flour and drug mills, and in any kind of light material. 

Of the light weights there are ten sizes made, ranging from 3^ to 10 inches 
on the belt. 

The 12 to 20 inch buckets are made with partial straight fronts. The 
following table gives sizes, weights and carrying capacities of the Due 
bucket : 

TABLE OF DIMENSIONS AND CAPACITIES. 



THE "light" bucket. 


On Belt (width). 


Projection (broad). 


Deep. 


Capacity in Cubic 
Inches. 


y/z 


2>^ 


2^ 


loK 


4 


2)i 


2% 


11^ 


4K 


2^ 


^H 


I7K 


5 


3X 


3% 


,24>^ 


iVz 


3% 


3K 


28 


6 


aVs 


iVi 


46 


7 


4^ 


4% 


65 


8 


sV% ■ 


aYa 


104 


9 


SU 


m 


131 




the " HEA\ 


'y" bucket. 




A% 


2^ 


% 


17K 


5 


3X 


3% 


24 K 


<!>% 


2% 


3Y% 


28 


6 


4% 


3% 


46 


7 


^Vs 


4% 


65 


8 


sVs 


4^ 


104 


9 


5^ 


4?^ 


131 


10 


(>% 


S% 


158 


12 


byi 


S% 


2l6 


14 


b% 


6K 


282 


16 


6^ 


6>^ 


395 


17 


7 


6^ 


436 



*T. F. Rowland, manufacturer, Brooklyn, N. Y. 



458 ELE VA TING, SPOU TING A ND CON VE YING. 

TABLE SHOWING CARRYING CAPACITY OF ELEVATOR BUCKETS. 





Speed 200 feet 


Speed 300 feet 


Speed 500 feet 


Size. 


per minute. 


per minute. 


per minute. 


No. Bushels per 


No. Bushels per 


No. Bushels per 




hour. 


hour. 


hour. 


5x4 


250 


371 


625 


6x4 


275 


412 


687 


7x4^ 


500 


637 


1,062 


8x5 


600 


goo 


1.500 


9x5 


650 


1,012 


1,687 


loxsYz 


850 


1,275 


2,125 


11x6 


1,105 


1.725 


2.b75 


12x6 


1,300 


1,950 


3.250 


14 X 6 


1,600 


2,400 


4,000 


20 X 6 


2,275 


3,412 


5,687 



Air-Blast Elevator. — So far, the air-blast system is very little used, 
and awaits development. In it we include fan-blast, fan-suction devices, 
and also the jet or injection principle. For elevating flour the fan-blast 




Fig. 310. 

elevator has the advantage of cooling the flour. Fig. 310 shows such an 
arrangement. 

Fig. 311 shows a proposed air conveyor arranged near a floating grain 
elevator in working position between a barge and a vessel ; the grain is 
drawn from the barge through the tube by suction until it reaches and 
mingles with the compressed air-jet within the contracted section of the 
elevator tube, being then forced up into a receiver in the upper part of the 
central vessel through which the grain falls in the usual manner, being again 
elevated into a tube leading to and terminating in the hold of the vessel. 
The shifting apparatus then forces the grain into and fills up all spaces be- 
tween decks. There is an air compressor or blowing engine, B, with suit- 
able air receiver, C C, in which the air should be kept at about 40 pounds 
per square inch. 



GRAIN ELE VA TORS. 



459 



Grain Elevators. — Figs. 312 and 313 show sectional end and side 
views of a large grain elevator. The ground dimensions of the building are 
330 feet by 86 feet, and the height is 136 feet. The -building contains 264 
compartments, of which 260 are bins for storing grain, and the other 4 
afford passage for the stairways, belts, etc. 

The inside dimensions of each bin are 9 feet by 9 feet square and 56 
feet high, including hopper. Below the bin hoppers is a story 16 feet high 
and extending over the whole ground floor of building. Through one side 
of this and about four feet below the floor is the railroad track, the cars 
coming in at one end of the building and going out on the other. The cars 
are unloaded by means of steam shovels, driven by shaft b, by which the 
grain is scraped out of the cars and dropped into the sinks c. There are 
eleven sinks and as many cars can be unloaded at once. In the bottom of 




Fig. 311. 

each sink are iron elevator boots in tanks of wrought iron calked so as to 
be water-tight. The elevator boots are provided with slides to regulate the 
feed, which can be operated from the floor above. 

The eleven elevators are marked e. The elevator head pulleys are 72 
inches diameter and 21 inches face, and the boot pulleys 24 inches diam- 
eter and 21 face. These boot pulleys are hung in universal bearings, which 
may be lowered at pleasure in order to tighten the belts. 

The elevator belts are 4-ply rubber, 20 inches wide, having on them 18- 
inch elevator buckets, very strong, and placed twelve inches apart. 

The line-shaft, e, in the attic rests in heavy universal boxes, and is 
provided with expansion couplings. There are eleven sleeves on this shaft, 
with babbitt bearings and spiral coupling jaws at one end. These sleeves 
are fastened in no way to the shaft, but have an elevator head-pulley keyed 
to each one. Fastened on the shaft with feathers are eleven coupling heads 
with spiral jaws which match those on the sleeves. These heads are thrown 
in and out of gear with the sleeves by means of forked levers and rings. 

30 



460 



ELEVATING, SPOUTING AND CONVEYING. 



When out of gear the sleeve with the pulley stands still and permits the shaft 
to revolve inside of it. By this means one or more of the eleven elevators 
can be run or stopped at pleasure without stopping the engine or line-shaft. 
The line-shaft, e, in the attic is driven by a 42-inch rubber 5 -ply belt. 




Fig. 312. Grain Elevator — End View. 

The belt is hung on a pulley 13^ feet diameter and 48-inch face, and is set 
in motion by a pulley 8 feet diameter by 48-inch face on the engine shaft,/, 
below, and is tightened by a 48-inch tightener. 

These eleven receiving elevators, d, discharge in the attic into eleven 
scale hoppers, /?, where the grain can be weighed and then spouted into 




www 






II pfT[!ff'[T^^^9^!l 



Fifi. 3«3— GRAIN ELE\ATOR 



SINKS, SPOUTING. 463 

the various bins below. If it is desired to work the grain over or ship it 
either by boat, car or wagon, it is spouted into the six sinks /, in which 
stand the iron boots of six elevators g, by which the grain is again elevated 
to the attic and thrown into the hoppers, k, from which it is dropped into 
the six scale hoppers, /, where it is weighed and thence spouted out into 
the shipping bins " m," which are only twenty-seven feet high, and thence, 
by the shipping spouts ?i, put outside of the building, either into boats, 
cars or wagons; or if it is only being aired, it is spouted from these bins back 
into the receiving elevators and again taken to the storage bins. The motion 
to all this machinery is imparted by an automatic cut-off condensing engine 
of 250 horse-power. The construction of the bins is very simple, they being 
built up of two-inch plank, ten inches wide at the bottom and reducing in 
width as they go up to eight inches, then six inches, and finally four wide at 
the top. 

Sinks. — In a custom mill the sinks or receiving hoppers may be placed 
over the separator, running up even with the grinding floor. There should 
be a stop slide so that the grain may be elevated for storage, without going 
through the separator. 

When the wheat is received it should be weighed; this may be done by a 
scale hopper on a truck. After weighing it may be run into the sink. 

Wheat may be taken into a receiving sink, a few feet from that end of 
the reel at which grain is received. This sink is suspended from the second 
floor and reaches nearly down to the lower floor ; the wheat is taken by the 
elevators to the highest point desired, and carried across by a conveyor. 

There should be a coarse screen placed over the corn and feed sink, 
about twelve inches from the top, to catch any large material which cannot 
be elevated. 

The stock hopper which will be placed over the chopping stones in a burr 
mill should have two slides, so that the grain may be changed, or run 'to 
another burr. 

The slides of stock hoppers should be so arranged as to be operated by 
the miller from the grinding floor. 

Spouting. — The grain or other material having been elevated by the 
endless belt and bucket system, may readily be sent where desired to points 
on lower levels, but not very far distant horizontally, by simple gravity, being 
directed by suitable spouting, generally air-tight, and preferably of large sec- 
tion, and having as steep pitch, as few angles, and as smooth interior surface 
as possible, to obviate clogging or pasting up. For operating, the usual form 
is rectangular, and the material employed is wood. Of necessity such spouts 
have waste spaces in their angles ; even the constant friction of use will not 
give them as smooth a surface as though metal were employed, and their put- 
ting up or alteration is an expensive task, demanding much time and skill. 
Such spouts are now being superseded by black sheet iron or tinned sheet 
iron spouting, which can be bought in sections of convenient length and 
diameter, and quickly put together. Round metal spouting possesses the ad- 
vantages of cheapness, smoothness of interior surface, and lack of angles to 
clog or paste up. Of course, it permits of less steep pitches being used, 
hence, allows more liberty to the millwright, as to the disposition of the 



464 



ELEVATING, SPOUTING AND CONVEYING. 



various machines and hoppers, than wooden spouts do. The slides for in- 
spection are simple curved plates working in slides. As far as possible the 




Fig. 314. 

mill should be arranged so that there shall be a minimum amount of cross 
conveying and re-elevating,' and a good system of spouting enables the ma- 



SPOUTING. 



465 



terial to be put where wanted, with a maximum expense for outlay and 
power. 



^ 



q 



1 ^ ^ ri r^ '> 1^ r\ /^ ^ ^ ^^ ^ /^ ^ ^ ^ ^^ J 

L '^ L L "* ' L L L '„ I L V L C V 'J L ' f 




The trough of the conveyor at the top of the mill may have short spouts, 
at intervals of four feet, which will take the wheat from the conveyors to the 



466 



ELEVATING, SPOUTING AND CONVEYING. 



bins. Each bin should have at its bottom short spouts to which may be 
attached an extension spout, to take the wheat to an intermediate hopper 
to the floor below. 

Endless-Chain Conveyors. — One method of cross-conveying is by 
means of traveling endless chains bearing slats which sweep along the ma- 
terial. Conveyors employing Ewart chain are constructed on two general 
plans ; one in which the slats are bolted on one side of the attachment links 
and chain either run in a recess in the centre of the trough if the upper run of 
chain is used, or ride on the top of the slats if the lower run is used. This 
form is adapted to use in places where the perfect cleaning of the trough is 
not required. In case the conveyor is to be used in conveying various kinds 




Fig. 316.— Double Flight Conveyor. 



of grain successively, the absolute cleaning of the trough is a necessity, and 
the slat and chain attachments are so made that the chain runs through the 
centre of the slat, which is lozenge-shaped, the longer diameter being at right 
angles to the chain and in the same plane as the chain. With this style of 
conveyor both the upper and the lower runs of the chain can be used at the 
same time, the upper run filling a bin and the lower emptying one. The 
shape of the slat is such that it will continue to fit the trough until worn out, 
and consequently no grain can lodge in the trough, but all is swept out. The 
wheels employed in this form are made with gaps, at proper intervals, so as 
to permit the projecting part of the slat to pass the wheel without interfering 
with the running of the chain. 

The Ewart Manufacturing Company, 253 South Canal street, Chicago, 
makes several sizes of chain especially for conveyors, and can supply the out- 
fits for mills, etc. 



HOLLOW SHAFT CONVEYOR, ETC. 



467 



Hollow Shaft Conveyor.— The Caldwell patent hollow shaft con- 
veyor* (Fig. 317), is a lap-welded pipe, made expressly for conveying pur- 
poses ; round, smooth, strong, and in equal lengths, for all standard sizes. 
The shaft is very small, whereby the material to be moved is brought so near 
the centre that the leverage and friction on the shaft are greatly diminished. 
A very small diameter conveyor is capable of doing a great amount of work, 
as the material is conveyed by the "flight" and not by the shaft. The larger 
the shaft, the greater the amount of frictional surface; the more power it takes, 
and the less material it moves. This conveyor is well constructed and eco- 




FlG. 317. 

nomical in its working. Its construction is on mathematical principles, 
giving good results with little space and power. It has no frictional or 
rough points to come in contact with the material, is smooth like an auger, 
can be run at a very high rate of speed, and will carry grain any distance 
required. It is made of wrought iron or of steel, galvanized iron or copper. 
Among its valuable features for bolting purposes are that bugs will not stay 
about it, nor will they deposit their eggs on it, and it does not carry the 
material up on the side of the box, but moves it along bodily. The hollow 
shaft conveyor is made right or left hand. 




F16. 318. 



Pitch, of Screw Conveyors. — On a right-hand conveyor the pitch 
of the flight gains to the right, on the left-hand conveyor the pitch gains 
to the left. A right-hand conveyor turning to the right, facing the driven 
end, carries or pulls toward the driven end ; a right-hand conveyor turning 
to the left, facing the driven end, carries or pushes away from the driven 
end. A left-hand conveyor turning to the right, facing the driven end, car- 
ries or pushes away from the driven end ; a left-hand conveyor turning to 
the left, facing the driven end, carries or pulls toward the driven end. Con- 

* Manufactured by H. W. Caldwell, Chicago, 111. 



468 



ELEVATING, SPOUTING AND CONVEYING. 



veyor boxes, with patent cleaning attachments and patent delivery gates, are 
made for use with these conveyors. The "flights" consist of a continuous 




Fig. 310. — ^Flexible Spiral Conveyor. 



spiral of sheet iron constructed of flat rings, with their inner and outer 
circumferences so calculated with reference to the diameter of the shaft and 
the conveyor that when opened out they make sections having a perfect 



/ 




Fig. 320. — Weston Differential Block. 



screw pitch. Such a conveyor is light, and has great carrying capacity with- 
out clogging or springing the shaft by its weight. 



DISCHARGE—FLEXIBLE CON VE YOR—HOIS TING. 



469 



Discharge. — Discharge openings should be arranged so as to perfectly 
free the trough. The openings in the bottom of the conveyor boxes should 
be on the carrying side of the boxes. Cut the bottom out including the 
corner piece, commencing at the lower edge of the opposite corner piece, 
and running it through to the side of the boxes. 

Flexible Conveyor. — Figs. 318 and 319 show a proposed chop con- 
veyor, in which there is a continuous channel or passage below the upper 
surface of the stone and containing a flexible spiral conveyor, driven by 
bevel gears. It is introduced here as hinting at possibilities in conveying 




Fig. 321. 

material " up hill and around corners," by flexible conveyors in tin spouts 
of round section. 

Hoisting. — For hoisting apparatus for the purpose of elevating ma- 
chinery or barrels of flour, it is desirable that there should be used some 
device that will give great power with great safety to the men operating it. 
In the Weston differential block the load is always suspended and can never 
run down. Hoisting is effected by pulling one side away and lowering by 
pulling the other. With the direct block one man can lift 1,000 pounds ; 
with geared blocks, 2,000 to 4,000 pounds, thus saving time and labor, with the 
greatest safety. They are compact, portable and applicable to many purposes. 
In Fig. 320 the hoist is shown in use for raising or lowering flour barrels 
in connection with a swinging crane, and in Fig. 321, raising heavy burrs. 



CHAPTER XXXVI. 

WEIGHING, TESTING, PACKING, BRANDING AND 

STORING. 



Scales— Grain Meter — Inspection of Flour and Meal— Packing — Economic Flour Packer — Tallies — 
Adjustable Tally— Electric Tally— Brands, &c.— Storage. 

As the preliminary operation of milling comes the weighing or measure- 
ment of grain. Deliveries from farmers' hands at elevators or nearest ship- 
ping points, and exchanges from storage warehouses to railway cars or other 
vehicles of transportation and of transfer to the miller require the determina- 
tion of quantities. Furthermore, after the grain has reached the mill there 
is still a system of balances to be carried out in order to maintain the pro- 
portions necessary for the admixture of grain and its conversion into flour. 





Fig. 322. — Dormant Flour-Packing Scale, 
WITH Drop Lever, for Millers. 



Fig. 323.— Dormant Scale, 
Iron Column and Sliding Poise. 



Following upon this conversion, another system of checks and tests becomes 
necessary, until at length the consumer who munches his loaf makes the 
final determination of every question as to weight or quality. 

Starting, then, from the beginning, the accepted standards of weight in 
pounds per bushel for the different cereals are as follows : Wheat, 60 ; corn, 
56 ; rye, 56 ; oats, 32; barley, 48 ; buckwheat, 60. 

We are thus brought at once to confront a method of weighing which can 
only be carried out by the use of scales. 

Scales. — Like other machinery, scales have been greatly improved in 
the last twenty years, and perfect as they now seem to be, improvements are 
constantly being made by enterprising manufacturers as practical use sug- 
gests. The old even-balance beam, with hopper on one end of the beam and 
standard 60s on the other end, has been supplanted by the more conve- 
nient compound hopper beams, using small weights in place of the cumber- 
some 60s, or platform scales with hopper on the platform, or the still more 
convenient wagon scales. The arrangement of the levers in the Forsyth 



SCALES. 



471 



scales* (Figs. 322 to 326), is such that the action of the weights placed 
upon them is direct, and the motion of the levers in weighing is down- 
ward, the same as if hung upon a steelyard beam. The pivots have steel 
bearing edges, and these rest upon flat steel plates. The levers are suspend- 
ed to the frame-work of the scales in steel-faced loops, which have steel 




Fig. 324. —Hopper and Elev.a.tor Scale, with Iron Column and Sliding Poise. 



guards at the sides to prevent friction against the sides of the levers. The 
platforms of the scales are held in position by check-rods, which prevent 
them from moving out of place, without interfering with the downward 
motion necessary in weighing. By these means the least amount of friction 
is caused, there being no lateral or twisting motion of the weighing ma- 




FlG. 325. — Hopper Scale fuk Grain, with Wooden Pillar 

chinery. The use of wagon scales for receiving scales at mills is more 
common than formerly, owing to the greater facility and rapidity in handling 
grain, as well as the less amount of labor required. These scales are made 
of different sizes, but with long platform scales (8x22 feet platform) the 
team is weighed with the load, and no variation from correct weight can be 

* Manufactured by Forsyth Scale Co., Chicago. 



472 



WEIGHI.XG, TESTING, PACKIXG, BRAXDING, ETC. 



made by the pulling or backing of the team, while the load is being weighed. 
Instead of the levers being hung by clevises from a hook or bolt, fastened to 
the bottom of the corner irons, the pivot of the lever rests in a saddle (with 
steel facings) which is suspended by two loops, passing up through the 
corner iron and hung to a cross-bar ; this cross-bar rests on a friction point 
which allows the scale platform to swing from this point. The result at- 
tained by this device is that in driving on or off the scale, the whole plat- 
form swings upon the four friction points, which do not allow the platform 
to move or grind upon the knife edges of the levers, which are thereby kept 
from becoming dull and rendering the scale less sensitive. 

Another feature is the manner of setting the platform pivots. These 
are inserted through the lever instead of being placed on the top. The 
platform bearings thus straddle the levers and are so formed as to make a 
housing for the pivots, so that they are protected from water running down 
upon them. The pivots of all large scales of this make are of wrought iron. 




Fig. 326. — Pit Wagon Scale. 



with square steel welded into the bearing edge. This manner of making 
the pivot enables them to be tempered to the utmost degree of hardness 
without impairing the strength of the pivot. The weighing beams of all 
wagon scales are made with a separate beam for deducting the tare or 
weight of wagon, leaving- the net weight shown on the beam. The forego- 
ing remarks apply particularly to pit scales or those having the working parts 
of the scale under the platform in a pit. Wagon scales of various sizes are 
are also- made wherein all of the weighing machinery is hung above the 
platform, the platform being suspended to it by rods. The machinery, 
being overhead, is kept dry, and by the use of long rods to suspend the 
platform to the pivots, the knife-edges do not become worn by the motion 
of the platform in driving on or off the scale. These scales are adapted for 
use with a wagon dump for unloading wagons, as there is nothing below 
the platform to interfere with the swing of the dump, and the platform is 
sufficiently wide to allow the dump to be placed in the middle of the scale. 
While a dump can be used with pit scales, its position has to be arranged 
with a view of cleaning the under-hung levers, but in the suspension scale it 



GRAIN METER. 



473 



can be placed anywhere in the platform. The ordinary hopper, compound 
beam, packing, dormant and portable scales and railroad track scales, on 
the suspension and pit plans, are constructed on similar principles. 

Grain Meter. — To make a barrel of flour, without knowing how many 
bushels of wheat it took and how much of every item of manufacture it 
takes to a barrel, is simply carrying on business blindfold. 




Fig. 327. 

The Standard Automatic Scale* (Fig. 327), for the rapid and correct 
weighing of grain and flour, consists of a discharge bucket suspended from 
knife-edge pivot points of an even-balanced beam, and divided into two 
equal compartments. 

Gravitating latches, pivoted to the suspenders hanging upon the knife- 
edge bearings, hold the bucket in position to receive the grain. 



* Made by the Simpson & Gault Manufacturing Company, Cincinnati. 



474 WEIGHING, TESTIXG, PACKING, BRANDING, ETC. 

Suspended from the opposite end of the beam, by the usual clevis and 
hook, resting upon knife-edge pivots, are the balancing weights. The weights 
are so arranged that the large weight, in connection with the small one on 
the supplemental beam, balance the empty bucket and the grain weight, the 
grain to be taken in the bucket at each dump. Immediately above the grain 
bucket is a spout tapering to a long narrow opening at the lower end, which 
delivers the grain into the bucket ; attached to the upper end of the spout is 
the spout from the elevator bin or cleaning machine. Two long narrow 
plates, closed by gravity, and working independent of the weighing mechan- 
ism, are loosely hung upon a small steel shaft on the front of the spout, and 
operated by means of fixed clutches. The larger one, which swings under 
the mouth of the spout, is called the main cut-off, the smaller one the sup- 
plemental cut-off. A grain-wiper on the lower mouth of the spout wipes off 
any grain resting upon the main cut-off each time it is withdrawn, and a 
similar wiper on the under side of the main cut-off performs a like service 
for the supplemental cut-off. Lifting links, attached to the scale-beam, rolls 
the shaft up and down as the beam rises and falls. 

When the bucket has reached its highest point, the cut-off plates are with- 
drawn from the mouth of the spout. 

When an amount of grain equal to the difference between the large and 
small weights has been received in the bucket, the bran and bucket descend 
until the small weight rests on the beam, and then receives an amount of 
grain equal to the small weight, and its downward movement is checked. 

The main cut-off plate closes to its fullest extent, leaving a narrow open- 
ing through which grain, equal to the small weight, is allowed to slowly pass 
until the bucket is full, when the supplemental cut-off completely checks the 
further flow of grain ; the bucket continues to descend until released by the 
clutches holding it in position, turns on its shaft, and the grain is discharged. 

The buckets work alternately in this manner until the grain supplied to 
the scale is exhausted. The turning of the bucket on the shaft and the dis- 
charge of grain from the full compartment causes the empty compartment to 
come under the spout to be filled in turn. 

The scale-beam of a machine weighing loo bushels per hour rises and 
falls only one-half inch. The manufacturers of this machine claim that it 
will weigh and wear correctly for twenty years. 

Two attachments, one called a "stop motion," the other "feed regulator," 
can be applied ; one for causing the machine to stop work when any desired 
number of fillings have taken place, the other stopping the flow of grain when 
the stone, upon the top of which the machine is placed, ceases running. For 
the purpose of weighing the exact amount of flour in uniform quantities 
(196 pounds) for a barrel of flour, it is a great improvement over the old 
method of weighing the barrel before filling, and then adding to or taking 
therefrom. 

Inspection of Flour and Meal. — " Good meal should feel smooth 
and not oily and clammy, sticking to the hand. If smooth, oily and sticky, 
it is too low ground and the stones dull. If part oily and part coarse and 
lumpy, and if it sticks to the hand, the stones have too much feed or are dull 



INSPECTION OF FLOUR AND MEAL. 



475 



and badly faced, or some furrows have too much draft, and are too steep at 
the back edge. The bran should be springy and elastic after the meal is 
sifted out. If the hand be shut up quickly on a handful, there should be 
a large portion that escapes between the fingers. When the bran is stiff and 
the inside white, it shows that the stones are dull or overfed. If some of the 
parts are thicker than the rest, there are some furrows that have too much 
draft ; are too deep and steep at the back edge ; and the feed is too little. 
Inspection of flour should be made with plenty of light, and as far as prac- 
ticable with the same degree of light, in order that the color may be more 
readily compared and judged." 

The color of flour increases in whiteness in proportion as it is reduced 
more finely. (Kick.) 

"Good flour should be white, with a slightly yellow cast. A bluish cast is 
a bad sign. There should be no black specks. On wetting and kneading it 





PAT.APRILI5?I879, 



Open. 
Fig. 328. 



Closed. 
Fig. 329. 




between the fingers it should work dry and elastic, not soft and sticky. Flour 
from spring wheat is apt to be sticky. On throwing a lump of dry flour 
against a dry, smooth perpendicular surface, it should adhere in a lump, not 
fall like powder. On squeezing some of it in the hand, it should retain the 
shape given it by the pressure." 

A handy testing sieve is made of a tin box, 8 inches diameter and 3^ 
inches deep, containing two taper rings, several rings between which the 
sieve cloth is placed, and by pushing one over the other the sieve is formed. 
There are nineteen changes of cloth, from No. 000 to No. 16 inclusive, con- 
tained in the case. 

Fig. 328 shows a very compact and convenient flour trier and inspec- 
tor, open ; Fig. 329, the same thing closed ; Fig. 330, the case. 

31 



476 WEIGHING, TESTING, PACKING, BRANDING, ETC. 

In ordinary bread-making one barrel of 196 pounds of bakers' flour makes 
from 260 to 300 pounds of dough, being a gain of from 32.6 to 53 per cent. 
In the baking each pound of dough loses about one and three-quarter 
ounces, or eighteen pounds of dough lose about one and three-quarter 
pounds, which is nearly the same thing. This brings this percentage down 
to about 28.6 and 46.5 respectively. 

Packing. — Foreign receivers object to the ordinary barrel as being 
likely to be short in contents through cooperage, sifting out, and so on. Flour 
in sacks stows closer and for this reason alone the freight is less than on 
barrels. Again, the barrel weighs 15 pounds for 196 pounds of flour and 
the sack only four to six. 

Barrels should be of white oak, well seasoned. The moisture from green 
wood has a very bad effect upon the keeping powers of flour. Flour keeps 
better in a cool, dry, airy room than anywhere else. Exposure to hot sun or 
wet, or being stored too near corn or oats, which are liable to become heated, 
will injure the wheat. 

Paper flour barrels are made from sheets of paper cemented together into 
a thick impervious sheet under an enormous pressure ; they are then pressed 
to shape and water-proofed, and, when finished, they weigh a little more than 
half as much as the wooden barrel. They may be shipped in very little space, 
120 barrels may be stored in the place occupied by 100 wooden ones. They 
roll straight, are nearly air-tight, and are impervious to dampness, and bear 
transportation through any climate, and will transport in cars or holds of ves- 
sels, unaffected by any odor of turpentine, or any such materials. The loss 
of flour in wooden barrels from the West to the seaboard is by some stated at 
four to six pounds and the cooperage upon them in transportation and in 
store, five to ten cents each. 

There are also barrels made from wood pulp. The body is in one piece, 
made from coarse wood pulp, under 400 pounds pressure per square inch. 
The heads are made in the same way. 

It is a common cause of annoyance and loss of material that barrel hoops 
will not stay put. By expansion and contraction of the barrel they are either 
eternally becoming loose and flapping about the barrel like a big collar on a small 
dog, or being burst from the barrel, leaving it at the mercy of expressmen 
and hoisting machines. An inventive Yankee has conceived the idea of sub- 
stituting for flat metal or wooden hoops those of corrugated iron wire ; the 
hoop consists of a corrugated iron wire hoop. The ends of the wire are 
fastened -by twisting. It is claimed for this hoop — first, that it will continue 
tight and intact under circumstances in which ordinary hoops would have 
hung loose or burst ; the wire stretching and expanding with the expansion 
and contraction of the barrel ; second, that there is less metal or wood in 
contact with the staves, and therefore less moisture and less corrosion of the 
hoops. It is said that ,the twisted joint does not interfere with the barrel 
being rolled or handled in the usual way. 

There is a growing demand for flour put up in sacks, and millers are 
paying more attention to this mode of shipment than formerly. Seamless 
cotton or jute flour sacks are manufactured, which have the advantage 



PACKING. 



477 



that, besides being well and closely woven, they have no seams which can 
rip and discharge their contents. 

Paper flour sacks are pf familiar use These were brought into being by 
the exigencies of the war, and are now made in such large quantities that 
by far the greater part of the sack-flour trade is carried on through their 
medium. Arkell & Smiths, Canajoharie, N. Y., are large manufacturers of 




Fig. 331. 

paper and cotton flour sacks, their factory having a capacity for producing 
30,000,000 per year. These goods can be recommended. 

Economic Flour Packer.— The improved Economic flour-packer, 
made by the Simpson & Gault Manufacturing Company, Cincinnati, packs 
in barrels or half barrels, and in bags of all sizes, whether of cloth or paper. 
It is of simple and durable construction, and is not liable to get out of order. 



478 



WEIGHING, TESTING, PACKING, BRANDING, ETC. 



It can be set up easily and conveniently, and will pack direct from the bolt 
as well as from a garner or flour-chest. The machine is 8 feet 5 inches high, 
driving shaft 7 feet 7 inches from the floor, and occupying two feet square of 
ground. The setting up can be done within two days, without even stopping 
the mill. Fig. 331 shows a hopper or flour-chest, as it should be constructed, 
on the top of the packer, and a barrel on the platform. The platform with 
barrel on it is raised until the cylinder, now above the barrel, reaches its 
bottom. The driving shaft is then raised, throwing the machine into gear, 
and the packing process commences. The flour inside the cylinder is forced 
into the barrel. The speed is fixed in accordance with the amount of work 
the machine is required to perform. At sixty revolutions per minute, 
from forty to forty-five barrels may be packed per hour. The flour is 
packed without gushing through worm-holes, etc., a difficulty most of the 
old kind of packers are subject to. It packs equally tight, and as the 
barrel fills up the platform recedes, and when the desired quantity is 
packed, a button attached to the platform strikes a trigger which throws 




Fig. 332. 

the machine out of gear. The barrel is then taken off, replaced by an- 
other, and the same process is repeated, as described. To change from 
barrel to bag, and reverse," the barrel cylinder and screw is taken off, and 
replaced by the intended size of each. The balance weight is changed, 
and everything else is the same as described when packing in barrels. The 
change of size requires only a few minutes' time. The machine will pack 
bags, according to the size and speed, in from three to four per minute. 

Tallies. — Tallying devices for registering the quantity of material 
packed are almost indispensable in any well-regulated mill. They may be 
simple tallying counters showing to the packing hands at the packing ma- 
chines the number of packages of output ; or they may register this in the 
office, by means of electric connections. Each tally may be of two kinds — 
adjustable to various sizes of packages, or fixed to tally only one size. 

Adjustable Tally. — The adjustable tally. Fig. 332, has the works in- 
closed in an iron case. The levers, A, B, and adjustable bolt, G, are the 



TALLIES. 



479 



attachments to the packer (the bolt, G, is secured to the platform of the 
packer), D is the gauge for adjusting the machine to tally eighths, quarters, 
halves or barrels; it is secured to rod C, and gives the rod a long stroke when 
barrels are packed, and a very short one in packing eighths. The knob, F, 
is used to throw the works out of gear, and prevent the machine from 
tallying when adjusting it from barrels to halves, quarters or eighths. The 
first dial to the right indicates the fraction of a barrel, and the other dials 
indicate the whole barrels. 

The Electric Tally. — This tally, Fig. 333, is well made, finely finished, 
and nickel plated, and covered with a glass globe. It is placed in the office 
or wherever most convenient. For large mills, the several tallies are gener- 
ally arranged under one globe. One battery will work a tally several hundred 




Fig. 333. 

feet from the packer. The battery needs but little attention, and a few cents a 
year will keep it in working order. For a short distance the tally will be con- 
nected to the packer by two lines of wire, one line will go from the tally to 
the battery and one from the battery to the packer ; the other will go direct 
from the tally to the packer. The attachment on the packer is to connect 
and disconnect, or vice versa, these lines once for each eighth of a barrel 
packed. When they are connected eight times in succession, a barrel is 
registered on the tally in the office; four times for a half-barrel, etc. If de- 
sired, the attachment on the packer can be inclosed in a box and locked up. 
The adjustable and electric tallies register eighths, quarters and halves as 
well as barrels. The device for changing these machines to tally barrels or 



480 WEIGHING, TESTING, PACKING, BRANDING, ETC. 

fractional parts of a barrel is so simple that it takes but a few seconds to 
make the changes. They always give the total number in whole barrels, 
and when they have tallied up to their capacity they will set themselves and 
commence over again. 

The " barrel tally" is made exactly like the adjustable tally, except that 
it is not adjustable to eighths, quarters or halves. It is made entirely of 
iron and brass, and warranted not to break or get out of order. It can easily 
be attached to packers, engines, skids, traps or anything else desired. It is 
largely used on bran packers to register the number of sacks packed out ; 
the sacks being weighed and a definite amount of bran filled in each. In 
such a case a barrel tally will save a great amount of figuring, and time in 
taking a yield. 

It is used in connection with flour packers only when barrels or packages 
of one size are packed. 

The barrel tally is supplied with an attachment for connecting with the 
packer, whereby, as soon as it is secured to the packer, it is in working order. 
Three sizes are made as follows : No. i, tallying 10,000 ; No. 2, 100,000 ; 
No. 3, 1,000,000. These tallies are made by W. N. Durant, Milwaukee, 
Wis. 

The attachment for the packer accompanies each machine. When 
desired, a wooden box to cover the tally and attachment will be furnished. 
This box prevents strangers from meddling with the machine, and it also 
forms a guard around the connection. With these tallies you are able to see 
at a glance the exact number of barrels packed each day, month or year, 
and in taking a yield much time and trouble is saved. They can be attached 
and put in accurate working order in fifteen or twenty minutes. 

By using an adjustable, electric, and in some cases only a barrel tally, a 
flour-book may be kept, which will be a positive check against any error. A 
tally will soon pay for itself, not only by preventing errors, but by its con- 
venience and amount of time and labor it will save. 

The cost of one of these tallies compared with the work it will do, is as- 
tonishingly small. For an adjustable tally the price being only I.0005 per 
barrel tallied for one year in a mill making 30,000 barrels. 

The electric, adjustable and barrel tallies are warranted to tally accu- 
rately and with reasonable care to out-last the packer to which they are 
attached. 

The principal advantages claimed for these tallies are : First, in register- 
ing in the office the amount of flour that is packed in the mill, and showing 
just when flour is being packed, and whether in eighths, quarters, halves or 
barrels ; second, these tallies, in connection with a grain weigher, flour and 
feed packers form a complete system of registering, which can be carried out 
as follows : Electric tally No. i in the office registers the number of bushels 
of wheat being ground ; tally No. 2, the flour packed out ; tally No. 3, the 
feed. With such an arrangement, an accurate calculation of the yield can 
be made at almost any time. Third, when it is desired to keep the different 
grades or brands of flour separate, an electric switch is used, and each grade 
is registered on a different tally, or, in connection with a grain weigher, sev- 



BRANDS, ETC.— STORAGE. 481 

eral kinds of grain can be run through the same weigher, and each kind 
registered on a different tally. 

Brands, Etc. — The barrel or package should be marked with the firm- 
name, place of manufacture, kind of wheat from which the flour was made, 
and the kind of flour — as low grade, wheat flour, straight, patent, etc. A 
perfect system of marking is thus required, and this is effected by proper 
brands and stencils, such as are made by S. D. Childs & Co., Chicago. Ship- 
ping receipts should indicate the character of the shipments, and conform to 
the marks on the bags or barrels. A series of rubber stamps, such as are 
made by S. Holderness & Co., Chicago, will be found useful for this purpose, 
or wherever a memorandum head is wanted. 

Storage. — Flour stored in barrels does not keep as well as in bags, get- 
ting musty, sour and mouldy, the gluten becoming soluble. Lack of air cir- 
culation causes this, as proved by the fact that the innermost flour is the 
sourest. 

Wheat should never be stored for any length of time ; and then rehand- 
ling or turning it from time to time is necessary. Long storage darkens the 
color of the grain and the berry loses its dryness. Wheat requires air and 
light and should be given frequent handling. 

Floors for storing flour must be strong, as the weight is extremely con- 
centrated. 

In the storeroom the wheat should not be deeper than two feet. 



CHAPTER XXXVII. 

CHANGING AND ALTERING MILLS. 

Changing Dress, etc., for New Process — Altering Mills. 

Changing Dress, etc., for New Process. — In changing from an 
old process to a new process burr milling, the first thing to be done is to 
change the dress of the burrs. Less land surface is needed for the new 
than for the old process, and we may lessen the land surface in two or three 
ways. One way is to sink a narrow furrow between each two of the old. 

If the mill being changed is a two-run mill, we must use one run for 
wheat and one for middlings ; and the middlings stone should have shal- 
lower furrows than that for wheat. 

The wheat stone, if four feet, may run 130 revolutions or less, and the 
middlings stone 140 or less. This will generally necessitate a change in the 
gearing or pulleys, because ordinarily we will find both stones geared to run 
the same speed. If it is not convenient to make the two different, then both 
may be run at the same speed — say 132 revolutions. This may make a 
difference in the speed of the other machinery ; but it will not be likely to 
make much, except in the bolts. 

Suppose it be intended to change a stone mill to the roller system gradu- 
ally, instead of making all the change at once. The first thing to do in 
the ordinary-sized mill will be to put in one set of smooth rolls and 
one set of bran rolls and to grind a little higher than usual. One set 
of 9 by 30 rolls will take care of the bran in a 150-barrel mill supposing 
that the grinding is medium high. One set of 9 by 30 smooth rolls will 
take care of all the germ and coarse middlings in the same mill. The 
next time that a change is made either the same year or another sea- 
son, a full set of reductipn rolls must be put in (less, of course, the 
one set of bran rolls already in). There must be also one more set of 
smooth rolls and more purifier capacity. Then, if the bolting were ar- 
ranged properly before, there would be needed only one or two changes in 
the cloths. If the bolting were not properly arranged before the change to 
the roller system, it would be absolutely necessary to change to modern 
methods. The cost of the first change, the addition of the smooth and 
bran rolls would be $450 (less 5 per cent.) for the bran rolls, and S350 
(less 5 per cent.) for the smooth. The setting up of these two sets of rolls 
should not cost over $75. It will be necessary to have one reel about ten 
feet long clothed with No. 8 or No. 9 cloth, costing say $60 to Sioo. The 
second year the five more sets (if for winter wheat) and one smooth set 
would cost for the machines $2,500 (less 5 per cent.), and the setting up 
extra. In putting in the bran rolls and smooth rolls it should be with the 



CHANGING DRESS—ALTERING MILLS. 483 

intention of adding the others later on. The shafting can be arranged for 
this, either on the other side of the mill, or driving from above, so as in 
neither case to interfere with the shafting of the stone. 

Altering Mills. — Brown gives an account of a three-run mill in 
Pennsylvania that he altered from old to new process : 

" The wheat-cleaning machinery of this mill consisted of one old-fash- 
ioned separation and a rolling screen. It had two run of four-foot stone for 
grinding wheat and one for corn. Its bolts consisted of four reels in one 
chest, two on each side. There was a bran duster in the mill, and this 
summed up the entire machinery of the mill for making flour. Years ago it 
used to run night and day, turning out a grade of flour that gave good satis- 
faction, and selling all the flour it could make at the mill door. When I ar- 
rived at the mill it was not running, and had not been for three months, the 
complaint being that the flour could not be sold, and if sold it was almost 
sure to come back. The first question asked was, ' Can you help us out ?' 
I thought I could, and we went to work. I immediately ordered a three-foot 
run of stone on which to grind middlings, a good smutter and brush machine 
to clean the wheat, new bolting cloths and a first-class purifier. I got the 
millwright to work making necessary changes, and had the millers take up 
the stone, and I assure you there was plenty of work for them to do. 
I inquired for the furrow and land sticks, and the board for the eye with 
draft circle on. The boss miller hunted around for awhile, and finally 
brought me some furrow sticks, saying that he believed they did not have 
anything else, at least he had never used anything further. Well, these 
furrow sticks were i;^ inch wide, and the stone had forty furrows. I made 
new furrow sticks two inches wide, land sticks to correspond, and fitted a 
board in the eye describing draft circle on it, one inch to the foot. I de- 
scribed another circle around the skirt of the stone about an inch from the 
edge, spaced off the sections, and then laid on my furrow sticks. When I 
found that the draft on those stones had always been calculated from the 
back edge of the furrow ; but at that, even, some furrows had a half inch 
more, and some a half inch less draft. The proportion of furrows to face was 
about equal. If either was greater than the other it was the face ; and a 
great deal of the face was in or near the eye. This, of course, gave a better 
opportunity to get the stone in proper shape than if the amount of face in the 
eye had been less after properly laying out the stone and getting the millers 
to work. I looked after the rest of the work in detail, and in a very short 
time we had the mill running with the following arrangement : 

" The wheat passed through the roller screen, thence to the separator, 
next to the smutter and brush machine — these last two being adjustable so 
that the wheat co'ildbe cleaned as desired — and then passed on to the stone. 
The stc^'-, ci3 remarked before, were two run of four-foot burrs, with the coil 
spring on the spindles, and running at a rate of 140 revolutions per minute. 
They had each forty furrows two inches wide, were medium close, and cal- 
culated to grind from six to eight bushels per hour. The chop from both 
run of stone was carried to the upper reel of the chest, on one side covered 
with six feet of No. 10 XX cloth, and the balance with No. 11 X, the reels 



484 CHANGING AND AL TERING MILLS. 

being twenty feet long. After the flour was cut off, all went to the reel below 
covered with six feet of No. 12 X, ten feet of No. 13 and four feet of No. i 
cloth. Flour was also taken from this reel, and the remainder, with the ex- 
ception of the bran which went over the end of the reel, passed to the upper 
reel on the other side, together with the chop from the middlings stone. 
This reel was covered with six feet of No. 12 X, ten feet of No. 14 and four 
feet No. 2 cloth. Flour was taken from this reel also, and the returns were 
returned to this reel. The middlings from the No. 2 cloth went to the reel 
below covered with No. 12 X cloth throughout, the dust being returned to 
the reel above, and the middlings going over the end of the reel to a first- 
class purifier covered generally, with Nos. 9, 6, 5, 3 and i cloth. The mid- 
dlings all ran together (except No. i) to the three-foot stone to be reground, 
and then to the bolt covered with Nos. 12 and 14 cloth, already mentioned. 
It will be observed that this mill makes only one grade of flour, which gives 
good satisfaction, and at present the proprietors are unable to fill all their 
orders, and are making a handsome profit. It will also be observed that while 
their bolting capacity is limited, they dust their middlings well, grind them 
separately, and are thus enabled to make a good straight grade of flour. 

" Since the above was written, I have had an opportunity of revisiting 
this mill, and of making some further improvements. With my advice they 
have added another run of stone, another reel twenty feet long and another 
purifier, same make. They are now bolting their middlings flour separately, 
which enables them to make a straight grade or patent flour, as they may 
desire, and is a much more satisfactory arrangement. 

" I was also informed by the proprietors that in running their mill eight 
months after it was repaired, they made a clear profit of S8,ooo above all ex- 
penses, repairs included. 

" Take a mill with two run of stone four feet in diameter, for wheat. 
This mill has two, and perhaps three reels, each twenty feet long. For the 
sake of being definite, let us presume that it has three reels, all in one chest, 
but that two are side by side, and one below and between the other two, each 
being independent of the other. Each run of stone has an elevator, and 
each elevator carries to a reel. The chop is thus divided between the two 
upper reels, which, if winter wheat is ground, are probably covered with 
Nos. 12 and 13 cloth in equal proportions ; and the lower reel probably has 
on six feet of No. 12, six feet of No. 9, four feet of No. 6, and thirty inches 
of No. 4, with No. 00 on the remainder, arranged in the above order from 
head to tail. This, is called the return reel, and bran, with all else except 
the flour that is taken out of the tAvo reels above, goes into this reel. 

" We will first take up a stone and commence reducing the face. No 
doubt the stone has as much land as furrow surface. Now, widen three fur- 
rows one-fourth of an inch each, on four sides of the bed-stone, making 
twelve furrows in all, and, leave them true and smooth. Dress the face of 
the runner sufiicient to keep it in face and put it down to work. Take up 
the other stone and dress the furrows in the runner and the face of the bed- 
stone, the same as in the first run. The next time the first stone is taken up 
reverse the order of work, furrowing the runner and dressing the face of 



ALTERING MILLS, 485 

the bed-stone, alternating in this manner through the year, and your stone 
will be in better order than by dressing the furrows once a year. After the 
furrows have been once gone over all around, it will not take so long to dress 
the stone afterward. In changing the dress of a stone in this way you do not 
take the stone off from its work any longer than for the usual time for dress- 
ing ; and after once going around on all the furrows, if you are satisfied that 
you have improved them, and think they have loo much face, as they un- 
doubtedly will have, you can make new and wider furrow sticks and go over 
them again. 

"We will now change the spout from one run of stone, so as to run the 
chop from both run into one set of elevators and into one reel. We will 
clothe this reel with eight feet of No. lo XX, and the remainder of it 
with No. 12 X cloth, and the lower or second reel with eight feet of No. 13, 
eight feet of No. 14, and four feet of No. i cloth. After cutting off the flour 
from the first reel, run the balance to the second reel, and taking off flour 
from this reel also, so far as it is good, you will get all your middlings through 
the No. I cloth, and the bran will pass over the end of the reel. You will 
now need a short set of elevators to carry the middlings from the lower to the 
upper reel on the other side, here to be dusted, ready for the purifier. Cover 
this reel with ten feet of No. 12 and ten feet of No. 13 cloth. The dust 
from this reel should be returned to the lower reel, not to the chop, and all 
returns, from whatever source, should go to this same reel and never be 
made to the chop, or first reel. The object of returning is to remove the 
specks, and the returns are usually made from a finer cloth than that at the 
head of the first reel ; and in putting material that has passed through a No. 
12 or No. 14 cloth back upon a No. 10 cloth, one can readily perceive the liabil- 
ity of getting specks. By throwing the returns into a fine cloth you are not 
so liable to get them ; and another reason for this is, that the proportion of 
fine and coarse material is about right as it leaves the stone, and to put the 
returns with it changes the proportion. The proportion has been changed, 
moreover, in the second reel, and there is need of all the fine material available 
to make it bolt properly. By proceeding in this manner, the first and second 
reels can be used for flour, and the third reel for finishing up on, or dusting 
the middlings. The middlings ought to go to two purifiers, the one follow- 
ing the other, but as we do not possess much money we will use only one. 
This is the first piece of new machinery we have had to buy, so we will get a 
first-class machine— one that has been thoroughly tested and is known to be 
a good one, and to have plenty of capacity to do the work. If you buy from 
an agent and he tells you that you need a machine to clean one hundred 
pounds per hour, purchase one large enough to clean two hundred per hour. 
It is a great mistake in buying purifiers to endeavor to get cheap ones, thus 
obtaining machines that are too small. If you are able to get two machines 
instead of one, it is economy to do so. All do not see it so at first, but are 
compelled to acknowledge it sooner or later. 

"After your middlings are well purified, they are, of course, ready to be 
ground, and ought to be ground on a stone dressed and kept for that purpose. 
But, for the present, and in order to economize, we will run them to the eye 



CHANGING AND ALTERING MILLS. 

of one of the wheat stones and grind them there. Thii is not the proper 
way to do it, but as we have no other stone, no money, and are intending to 
make only a straight grade, we will allow you do so until you see the benefits 
of this much of the new process. Of course, in grinding the middlings in 
this way, they must be bolted with the chop also, which is not right. 

" But when you have seen the result of your mill so far improved, and 
think you would like to take a step farther in advance, procure the best close 
old stock three-foot upper-runner you can find, and put it in a strong husk 
frame. Dress it as nicely and smoothly as possible, taking all the pains you 
are capable of, using the same kind of dress as in your wheat stone, and 
dressing it in the same way, with this exception : do not have the furrows so 
deep. Take great pains to have it level, in true face, in perfect tram, in both 
standing and running balance, and do not run it to exceed 140 revolutions 
per minute. Use the spare set of elevators you had left after making the 
change before mentioned, and if you do not feel able to add to your bolting 
capacity, run the meal from the middlings stone to the second or lower reel 
to be bolted there. This will be more satisfactory than before. When you 
are prepared to increase your bolting capacity, put up a single reel twenty 
feet long, or two reels twelve feet long, using Nos. 12 and 13 cloth. 

" By the time you have progressed this far along, you have got your 
stone dressed so that you are making more middlings, and need another 
purifier to follow the first one. You are granulating your wheat and mid- 
dlings separately ; you are bolting separately, and making two grades of flour, 
the poorest better than the best you ever made before, and are prepared to 
take off five, ten, fifteen, twenty, twenty-five or perhaps more barrels of 
patent flour from your middlings bolt, mixing the remainder with your first 
run in a conveyor for that purpose, or, if you wish to make only a straight 
grade, run the whole product of flour from your middlings bolt into the con- 
veyor and mix with the first run." 



^m^ 



CHAPTER XXXVIII. 

MILL W RIGHTING. 

Tools— How to Treat and Use a File— Marking Oflf— Timber Joints— Halving Together— Open Mortise 
and Tenon Joints— Regular Mortise and Tenon Joint— Blind Mortise and Tenon Joint— Dowel 
Joint— Various Methods of Setting the Bevels of a Hopper — Building an Overshot Wheel. 

Tools. — We will lay down a list of tools for millwrighting work, giving 
the kinds and sizes most needed in every-day work. Of course there will 
be some special cases where extra large or extra small tools will be needed, 
as well as other tools than those laid down ; but the following list is believed 
to be about right : There will be needed a common axe, for roughing out 
logs, and a broad axe and an adze for dressing them ; an adze, a set of 
planes, embracing a jack and fore plane, smoother, and a "nigger shin," 
a tool little if at all used by carpenters. Its function is to work out curved 
surface.';, as segments of water-wheels, etc. It is about as long as a smooth- 
ing plane, and it might be made from that tool. For chisels, there 
would be needed a set of firmers, which may contain as many as fifteen 
sizes, of which about eight will be needed in every-day work, these being 
2-inch, if, i^, I, f, "I and ^. There must be some large framing chisels, 
running by half inches from 3 inches to i inch inclusive. There must be 
a brace and set of auger bits of sizes from i-J inches down to ^ inch inclu- 
sive, and some bits for screws. There will be required a set of augers from 
f up to 2 inches inclusive, and a 14-inch monkey wrench. Two screw- 
drivers will be enough, one 12 and one 16 inches long. There must be a 
good tri-square and a 24-inch graduated iron square, also a 12-inch adjust- 
able bevel square. For marking out, there must be a scribing awl and 
a chalk line. Get a hickory ma:llet for use with the chisels ; lignum- 
vitse is too hard. This mallet should weigh about i^ pounds, and be in 
dimensions about 6x3x4 inches, having its sides nearly parallel and the top 
wider than the bottom. There must be one hammer i^ pounds weight, with 
one end round and the other flat ; and a claw hammer (about No. 8) weigh- 
ing three-quarters of a pound or less. There might be a hand axe with a 
face 6 inches long and a handle 14 inches long. For a level, one 24 inches 
long will be right size, and there should be a small level to use in connection 
with the iron square. There must be a pair of " trams " to draw large 
circles, and a pair of 6-inch compasses ; also one pair of 12-inch and one of 
16-inch. This last will strike a circle thirty-two inches in diameter, and 
anything larger than that the trams will lay out. There should be a good 
plumb-bob, having the top of the bob screw out, as this kind centres the line 
better than the others. In the way of saws, there should be a 14- inch back 
saw, a regular 42-inch rip saw, a cross-cut of the same length, and a 



488 MILL IV RIGHTING. 

14-inch compass saw. To sharpen these there will have to be a 3^-inch saw 
file for the back and compass saws, a 4-inch saw file for the cross-cut and a 
5-inch for the rip. Bear in mind that a three-cornered machine file and a saw 
file are very different. I omitted mention of a lighter hammer for key seat- 
ing, and weighing say three-quarters of a pound. In the way of cold chisels 
there should be all sizes from ^ inch to i inch. There must be two wood 
files, one coarse and the other fine cut, of lengths 14 and 12 inches. There 
should be two flat files of the same sizes, and coarse and fine, for iron work. 

There will be required gouges from ^ inch to i^ inches inclusive. One of 
the most useful things that the millwright can have is a slide rule, by 
which so many constructions and calculations can be made. Of course, 
there must be common and lumber pencils, and the regular "four-fold" two- 
foot rule. Then there must be provided suitable bench, carpenter's vise, 
machinist's chipping vise (which will answer for filing also), and sawing 
trestles. 

Ho^W to Treat and Use a File. — " Probably with all the improve- 
ments in planers, milling machines and similar tools, and with all the increas- 
ing uses of the grindstone and emery wheel, the time will never come when 
the file will cease to hold a prominent position in the machine shop. It is al- 
ways ready for use, always handy, is adapted to a great range of work, and 
is essentially a hand tool, responding instantly to the demand of the work- 
man. It requires enough skill in its use to justify a proper pride in the 
workman who can do a good vise job. It is important, therefore, that the 
apprentice should early be taught the proper care as well as the proper use 
of the file. There is no surer indication of the sloven in the shop than a 
disorderly array of files on the bench. 

Files ought to be properly handled. A chisel handle is not a file handle, 
nor is a pine stick, nor a section of a broom handle. The handle should be 
proportioned in size to the size of the file and the description of the file. A 
twelve-inch bastard file ought to have a larger or at least a longer handle 
than a twelve-inch finishing file. A slender square or rat-tail file should 
have a smaller handle thnn a coarse or large file of the same length, because 
the feeling in the hand when grasping the handle suggests or impels the 
degree or force used in the act of filing. With a small handle, the work 
man has a suggestion of "delicacy in using. The handle should never be 
driven up to the end of the shank ; that is, the shank should remain out of 
the handle half an inch, or thereabout. The handle should not be driven on 
the shank by blows on the end, the file resting on the bench or vise, either 
with a hammer or mallet. The handle should not be marred out of shape, 
nor defaced by bruises ; such imperfections or injuries are repellant to the 
feeling of the hand. Bore the tang hole with a gimlet, and slightly ream the 
hole with a taper reamer ; enter the tang enough to hold it, turn the file handle 
down, and, while having hold of the handle, rap it two or three times on the 
bench. There may be occasions when a blow or two from the hammer may 
be necessary to fix the handle securely. If so, hold the file by the handle, 
the file downward, and rap with the hammer on the end of the handle, but 
be careful not to mar the handle. See to it that the handle is in line with 



HO W TO TREA T AND USE A FILE. 489 

the file, and not at an angle. It may be easy to file with the handle rising at 
a slight angle, but when the other face of the file is used the downward angle 
is anything but pleasant. Good work cannot be done with the handle and 
file out of line. 

It is a good plan to keep the handles of the files off the bench. To do 
this, fix a narrow rib of wood on the top of the bench, far enough from the 
edge to receive the file near the tang and not allow the handle to project 
beyond the edge of the bench. If the strip is half an inch high it is enough, 
as it is only necessary to keep the files from the bench, so as not to get fil- 
ings or other matter on the handles, and to enable the hand to pick them up 
readily. Some use a wire instead of a rib ; wood is preferable. It is a still 
better custom to have a board, twelve by fourteen inches, with the rib 
tacked on one edge or end, to place on the bench, at the right hand of the 
vise, to receive the files, and to be removable. It is well to have the bench 
drawer arranged to receive this file platform, with its files, at the close of the 
day's work, or to have cleats under the bench to receive it as a shelf or 
drawer. It is abusive to files to pick them up, one by one, or in a bunch, 
and dump them, rattling and scratching, helter skelter, into a drawer, on top 
of cold chisels, centre punches, &c. Besides this orderly arrangement of files, 
ready for use, is a great convenience, and the board or tray can be kept much 
cleaner than is possible to keep a bench, and may be replaced readily, if 
broken. It should be of soft, clear pine, planed smoothly. 

The practice of heating the shank of a file, and using it to burn its way 
into the handle, is not only slovenly, but is wasteful. This heating destroys 
the tenacity of the wood, and the handle soon splits ; and a split file handle 
is good for nothing except kindling. Never mend a file handle ; it is even 
more useless than to mend rubber shoes or boots. Soon as a file handle 
cracks, throw it away. Wire-wound or string-tied file handles are an abom- 
ination. 

About handling the file — working with it — few textual directions can be 
of use. It may be said, however, that the file is essentially a cutting tool, 
not a mere abrader. The action of filing is not a mere swinging of the arms 
with a file held suspended in the hands ; neither is it a rubbing motion, as 
with an emery stick. While the particles of emery present angles in every 
direction, the file has well defined teeth intended to cut but one way. The 
forward motion of the file is the working motion ; the backward motion is 
merely a recovery for another stroke. But to draw a file straight is an art only 
to be aquired by practice ; and this practice is absolutely required if the appren- 
tice is ambitious to become anything but a botch. His hands also must feel 
the file during the entire stroke ; any lodgment of particles in the teeth must 
be instantly detected, and the obstacle removed, or a deep scratch is the re- 
sult. In draw-filing there is still more necessity for patient practice. To the 
ignorant looker-on, nothing is simpler or easier than draw-filing ; in fact, no 
use of the file is more difficult to acquire. Either the right or the left hand will 
push the faster, to the ruin of the surface. The lines in draw-filing must be 
parallel, and in the direction of the job or piece. It will not do to have a 
"catty-cornered " finish or a " cross hatcheling " on a draw-filed finish. In 



490 MILL WRIGHTING. 

this parallelism of the lines and their uniformity consists the beauty of this 
finish — a finish never yet equaled by any polishing wheel or hand rubbing 
with abrading substances. It is the perfection of workmanlike finish. A high 
polish may delight the unmechanical eye, but the draw-file finish is a satis- 
faction to the mechanical taste." — Boston Journal of Covwierce. 

Marking Oflf. — Even in so small things as using a chalk line to mark 
off witness lines there is a right way and a wrong way to go to work. It is 
desirable to make a quick job, a neat job, and to preserve the line of the 
chalk. 

The chalk line is a small, strong cord, well twisted, which, after being 
well chalked, is tightly stretched between two points and "snapped," so as 
to leave a straight, well-defined chalk line by which to work. The chalk 
should be really the shape of a wooden bung, the flat side only used. The 
line has a loop at one end through which an awl is passed, the awl being 
stuck exactly in one of the places between which the chalked line is to be 
made. The line being tightly drawn with the thumb and finger of the left 
hand, the chalk is held in the right hand, and the line bent on the chalk, 
keeping the flat side of the chalk parallel to the plane in which the cord lies, 
and a step being worn off that flat side in a regular curve, so that after sev- 
eral rubbings the entire surface of the flat side of the chalk has been worn 
away to a definite depth, when the operation may be performed in the same 
way. The sketch (Fig. 334) shows the proper section of the chalk when 
about half worn across. By this method the entire length of the line will be 
properly chalked, neither too much nor too little, and the chalk will not be 
wasted. Having chalked the line, stretch it tightly so that it will cover (not 
merely lie alongside of) the other point. The line being placed against the 
board or timber, near its end, with the left thumb, it may be drawn tight 
with the left fingers. 

One eye being shut and the other placed above the line, this last 
should be grasped with the right thumb and forefinger about a foot from the 
left thumb, and the little finger of the right being placed upon the board to 
steady the hand, raise the line vertically and then let it go. If the line does 
not sight straight when raised, it has not been raised vertically and will not 
make a straight line. 

In some cases it is mor-e convenient to stand at the side of the board, in 
which case the left hand and eye are to be used as before, and the line 
grasped with the right forefinger and thumb, with the right palm down and 
the backs of the fingers to the front, the surface of contact of the thumb and 
forefinger being kept vertical and parallel to both straight portions of the 
line, it should be snapped as before. 

To make a crooked chalk mark with the line, stretch the line between 
the tvyo points as before, but when raising the line carry it to right or left as 
desired, and let go. » 

In some instances it is not convenient to use the regular marking tool, or 
very accurate work is not needed. In such a case, to mark a line upon a 
board or timber, parallel to the edge, and at some given distance from this 
edge, the ordinary two-foot rule may be used, being grasped with the left 



TIMBER JOINTS. 



491 



hand, and rested upon the board, its length square with the edge, and the 
end at the desired distance from the edge. Then pressing the rule upon the 
surface of the wood with the left thumb, and resting the left forefinger 
against the edge of the board, the second finger of the right hand being 
placed upon the board and against the end of the rule. The scriber or 




Fig. 334. 



other pencil should touch the end of the rule, the second finger on the sur- 
face of the wood; then sliding the marking tool and the rule along the sur- 
face, the line will be at the desired distance, and parallel with the edge of 
the board or timber. 

Timber Joints. — The following paragraphs give detailed directions 
for making in the best manner the more important timber joints, large or 

32 



492 



MILL WEIGHTING. 



small. Where the instructions refer to placing the pieces in a vise, of course 
this will be understood as applying to small pieces only, for light joinery. 

Halving Together, — We will suppose that two sticks are to be 
halved together at their ends. We will consider that they have been dressed 
to dimension ; the first thing is lining out. The tri-square is to be placed 
upon one of the timbers, with its beam resting along its one surface, the 
tongue upon the top, and the edge a little less than the width of the other 
stick, from the end of the stick being marked (Fig. 335). We had better call 
one stick A, and the other B ; and suppose that we are marking A first. 
Place B right side up, upon A, with one long lower edge touching the edge 
of the square, and its end flush with the vertical side of A ; slide the tri- 
square together along the top of A, until the vertical side of B is flush 
with the end of A. Take off B, and then, with a sharp knife line across A, at 
the edge of the square, running this line half way down each of the long 




Fig. 335. — Halving Together. 

vertical sides of A. Make smaller lines upon the lower side of the long ver- 
tical side of B, using the upper side of A as a measure, and turning the tops 
of both pieces down to draw the lines easily. Then, with the gauge, having 
the spur set to mark a distance from the head equal to half the common 
height of the timbers, gyide the gauge head by the upper surface of each 
timber in turn, gauging along the long vertical side of each. To saw across, 
put each beam in turn in the mitre box, or in the bench vise, or against the 
bench hook. Use a fine-tooth back saw, taking care not to remove any of 
the knife-marks 

There are three methods of taking out the wood between the marks. 
One is to put each stick upon its side and fasten it with a wooden hand- 
screw to a board upon the bench, then split off chips, parallel with the grain, 
with a paring chisel wider than the cut to be made, inclining the tool so 
that the chips shall grow finer as the tool cuts deeper, and giving it so much 
inclination that the chips shall not split below the three gauge-marks. After 
the last cut agrees with the upper gauge-mark, turn the stick and repeat the 
operation. There will then be a ridge running lengthwise of the stick. The 



MORTISE AND TENON JOINTS. 



493 



outer end of this ridge may be taken out with a wide chisel ; then, turning 
the stick again and fastening it as before, take a narrow paring chisel and 
bevel the inner end of the ridge so that it will end in a straight line joining 
the corners of the knife-marks and the gauge-marks. There will then be a 
pyramidal ridge, which may be nearly all split off, and the rest pared off. 

Another way is to place each stick upright in the vise and cut along the 
gauge-marks with a sharp, medium fine rip saw, almost to the cut made by 
the back saw, paring the surfaces with a chisel to finish, or paring the wider 
surface with a small plane. 

Another method, with the stick upright, is to cut with a fine rip saw 
close to the gauge-marks, down to the back-saw cut, and square out the 
corner with a narrow paring chisel. 

Another way, which will answer in some cases, is to lay the two ends that 
are to be halved together, holding them firmly together, and then, having 




Fig. 336. — Open Single Mortise and Tenon. 



scribed off on the side of one of them a square or a four-sided figure cor- 
responding to the end of one timber, and having divided these in half 
parallel with the length of the stick, and having scribed off the lines upon 
the ends of the timbers, take a fine rip saw and cut down clear to the depth 
of the scribed figure on the side, and then, with a fine crossing saw, cut 
from one side of the two timbers down to the cross line. This will make the 
two timber ends just alike, each one having, one half removed, and the two 
halves fitting together. 

Open Mortise and Tenon Joints. (Figs. 336 and 337). — One of the 
sticks will contain the mortise and the other the tenon ; we will call the first 
M and the second T. The first thing is to line out the mortise. Mark the 
length by laying the tri-square and the tenon stick upon it, marking each 
edge on the top of M with a sharp knife. (Knife-marks are the best for 
several reasons : they do not rub out, they can be made close and true to 
the edge of the square, and they have no appreciable width.) Then, resting 
the beam of the tri-square upon the top of M, and with the edge of the 



494 



MILL WRJGHTJNG. 



blade at each of the points in turn, mark on the sides of M the place for the 
end of the mortise, making these knife-marks larger than the ends of the 
mortise. The length of the tenon is got by laying the tri-square and the 
mortise stick upon it, then lining across the top of T, then resting the beam 




of the square on T, laying down both sides from the ends of the lines of the 
top, making a straight mark across the beam, and the stick will then have 
been lined all the way around. Then, setting the gauge spur one-third of 
the thickness of the piece, rest the gauge head upon the top of M and T in 
turn, gauging along the sides as far as the cross line before drawn. Next 



MORTISE AND TENON JOINTS. 495 

gauge across both ends of the flush pieces. Then, moving the gauge spur 
back to two-thirds the thickness of the piece, gauge along the sides and 
across the ends of both pieces near the other gauge line. 

We now have both the tenon and the mortise marked out. To cut the 
tenon a fine-toothed saw may be used. Cut nearly to the line, and make the 
surfaces true by a paring chisel ; or a mallet and a chisel may be used 
entirely. 

There are five ways of roughing out the mortise : i. The stick may be 
placed upon the bench, side up, and fastened with a wooden hand-screw. 
Then, with a mortising chisel one-eighth inch narrower than the mortise is 
thick, placing the cutting edge centrally to the thickness of the mortise, and 
about one-fourth of an inch from the end of the mortise, holding its straight 
face upright, and next the flush end of the mortise, and being careful not 
to tip it sidewise, drive it in with the mallet. Cut half down through the 
depth of the stick. You will find that the chips and the chisels will work 
out easily from the open end of the mortise. Each cut should be taken nearer 
to the blind end. You must not cut closer than one-eighth of an inch to the 
blind end of the mortise in this roughing out. Then turn the stick over, the 
other side up, and do the same thing, ending as before, about one-eighth of an 
inch from the blind end. Then, turning the chisel so that the bevel face is 
next to the flush end of the mortise — that is, the straight face of the chisel 
next to the blind end of the mortise, and, holding the tool vertically, trim 
nearly to the end of the mortise. 

2. The second way of roughing out the mortise is to take a medium fine 
saw and, placing the stick end up in the vise, saw nearly but not entirely 
down to the gauge-marks, being careful not to cut into them at side or 
bottom. The wood between the saw kerfs should be taken out with a nar- 
row mortising chisel. 

3. Use a bit of a diameter slightly less than the thickness of the mortise, 
and bore all the way through, beginning near the open end and working back 
to the blind end. 

4. Take the bit last mentioned and bore one hole all the way through the 
mortise, near the blind end, taking the rest of the wood out by two saw cuts 
lengthwise. 

5. With the stick upright in the vise, saw out the stuff close down along- 
side of the marks and very near to the blind end, then take out most of the 
wood with a narrow mortising chisel. 

To finish, after any one of the first four methods, take a paring chisel as 
wide as the mortising chisel, and square out the blind end and bevel the 
sides to end in a line joining the corners where the knife-marks and the 
gauge-marks meet. Then take a wide paring chisel and bevel the sides of 
the outer edge until the bevels end in the gauge-marks, then split and pare 
to the planes of the gauge-marks. 

The open double mortise and tenon joint is made in the same way 
as the open single, but the thickness of each mortise and tenon is one- 
fifth the thickness of the sticks instead of one-eighth as in the single open 
joint. 



496 



MILL WRIGHTING. 



Regular Mortise and Tenon Joint. — The open mortise and tenon 
joint (Fig. 338) is a development of the method of halving timbers together. 
The double open mortise and tenon is a variation of the open mortise and 
tenon, and the regular single mortise and tenon is a development of the open 
mortise and tenon. To make the regular style, lay the mortise stick, which 
we shall call M for short, upon the bench, with the top up. Put the tri-square 
blade so that its edge shall be directly over one end of the mortise; mark 
with a knife a point in each edge of the top at the edge of the blade. 
Then, without changing the blade, rest the tenon stick (which we shall 
call T), top up, upon M, its flush end flush with the side of M, and one of 
its lower edges touching the edge of the blade. Mark a point in each edge 
of the top of M, at the lower edge of T, and over where the other end of 





Fig. 338. — Regular Single Mortise and Tenon. 



the mortise is to come. Then square down from the four marked points in 
the top of M and upon the sides of M, making four marks to show where 
the mortise ends will come. Then mark off upon T the length of the tenon, 
which will, of course, be determined by the thickness of M, and line all 
the way around. Then, with the gauge, just as in making an open mortise 
and tenon, gauge the sides of both mortise and tenon. 

To get the wood out of the mortise there are three ways : 

1. Bore holes all the way through M, on the central line of the mortise, 
and nearly to its extreme ends. 

2. With a sharp mortising chisel, slightly narrower than the mortise end, 
cut across the grain one-eighth of an inch from the end of the mortise, the 
chisel being held straight upright with its straight face next the narrower end 
of the mortise. This will leave a gap in the wood. Moving the chi.sel 



MORTISE AND TENON JOINTS. 



497 



edge slightly toward the centre of length of the mortise, cut again, and so 
on until there is at each end a gap large enough to work with, then turn the 
piece over and do the same thing from the lower side. This will leave the 
gaps all the way through, and a centre piece of wood remaining. 

3. The third way is to take a small bit and bore all the way through the 
wood, near the end of the mortise ; then take a key-hole saw and cut around 
the four sides of the mortise, rather close to the witness lines, but not touch- 
ing them. 

To remove the rest of the wood, that is, to finish the job, there will be 
needed two paring chisels, one rather narrower than the sides, and the other 
rather less in width than the ends of the mortise. The ends should be 
squared out clear to the knife-marks, the sides being beveled to end in 




Fig. 339.— Blind Single Mortise and Tenon. 



straight lines joining the end corners. Then, with a wider chisel, the sides 
may be beveled to the gauge-marks. Then the ridge may be split away, 
and the sides pared to the gauge-marks with the wide chisel. One of the 
straight edges of the chisel may be used to test whether the paring is being 
done accurately. 

Blind Mortise and Tenon Joint. — The blind mortise and tenon is 
the same as the regular mortise and tenon, except that it does not go entirely 
through. It is shown in Fig. 339. Sometimes a blind mortise and tenon 
joint is made at the end of a brace to render it rather more resistant to 
lateral pressure. It is sufficiently explained in Fig. 340. 

Dowel Joints. — The regular dowel joint (Fig. 341) needs less ex- 
planation than the half-blind dowel. To make this last we pick out the 
best piece for the face ; lay off upon its inner wide surface, a distance from 
the end equal to the thickness of the other piece, and line across, then, with 



498 



MILL WEIGHTING. 



the knife and tri-square, carry this line all the way around. Gauge across 
the end of the best piece, one-quarter the distance from its flush face, and 







carry this last line along the narrow sides as far as the first line drawn ; cut 
away the part thus marked out ; then, holding the end of the other piece in 
this rabbet (using the vise), bore three or more holes through the end of the 



DOWEL JOINTS, ETC. 



499 





7\ 



p- 



Fig. 341. — Regular Dowel Joint. 




7L 



7k 



Fig. 342.— Blind Dowel Joint. 



500 



MILL WRIGHTING. 



piece, running through about an inch into the end of the first, or best piece. 
These holes we have for the dowels or pins, which should be glued in place 
with hot glue. The proper size of dowels for a |^-inch board, is -^-inch. 




Fig. 343.— Blind Dowel Joint with Mitre. 

Fig. 342, shows a blind dowel joint, and Fig. 343, shows a blind dowel 
joint with a mitre. 




Fig. 344. 

Various Methods of Setting the Bevels of a Hopper.* — 

First strike out the square of the hopper to any scale you wish to work by. 

* Adapted from Bookwalter. 



SETTING THE BEVELS OF A HOPPER. 



501 



Intersect the square both ways in the centre, and strike a diagonal as shown 
at A ; scale off on that line from centre, B, to C, the depth of hopper. Set 
your dividers at centre, B, and depth of hopper at C, and swing the dividers 
round until they intersect perpendicular line D. Draw a diagonal line, E, 
from that point to centre line, F. Set your dividers on line E, so that by 
striking a circle they will intersect perpendicular line D, and the outside line 
of square of hopper ; strike a right-angled line, G, from centre of line E, 
until it touches the circle ; then drop a perpendicular line, H, down to in- 
tersect diagonal line A. Carry that line at right angles until it intersects 




Fig. 345. 



perpendicular line D ; then drop a perpendicular line, I, down to line A, and 
draw line J to intersect at line D, as shown. It is by lines I and J that you 
set your bevel square to cut the corners of the hopper by. 

To get the length of sides of corners, strike a line, K, from C to corner 
of square. 

This gives the length of line, L M, intersecting perpendicular line D ; 
and this determines the width of board required, from which to make the 
hopper. You can make any allowance at point M for hole in hopper that 
is thought suitable. To get the corner strip to fit the corners, make diagonal 
line, N, from corner to centre. Set your dividers on line N, wherever 
you please, and strike a circle that will just touch K. Draw a line, O, 
through the centre of the circle at exactly right angles to line N, until it in- 
tersects the two outside lines of hopper. Draw angular lines, P P, to inter- 
sect the circle on line N. This is where the bevel is set, around lines P P, to 



502 



MILL WEIGHTING. 



get the angle of corner strips. The draft should be carefully and correctly 
made, and the edges of the boards exactly square where the bevel square is 
applied to cut the corners. The method here described is applicable for any 
size, depth or width of hopper required. (Fig. 344.) 




Fig. 346. 

Another Method. — Plan the hopper on a large scale. Draw the diagonals 
A C and D B, also the perpendiculars E F and G H. From the centre, L, 
lay off one of the diagonals the distance, L I, equal to the vertical depth of 
the hopper. Connect D I ; then the angle, D I A gives the bevel to be 
applied to the edge of the board to cut the required joint between two ad- 




FlG. 



jacent sides. Next make D K equal D I and draw D K and A K. Then 
will the angle A D K or K A D give the required bevel to be applied on 
the surface of the board in order to cut the sides of the proper slope, and 
give them the proper inclination. (Fig. 345.) 

A Third Method. — Ascertain the size you want your hopper on the top, 
then make a draft according to the size, as A, B, C, D. Then find the depth 



SETTING THE BEVELS OF A HOPPER. 



503 



you would have the sides, as H E. Draw one side piece, C E D. Extend 
the line C D any distance, as to J. Then draw a line from the point E, 
perpendicular to the line D E, until it intersects C D, say at F. Then set 
the dividers with one point at E and the other at F, and sweep E G until it 
strikes the line A D. Now draw the line G F. The angle A G F would 
be the angle required to set the bevel for the mitre of a hopper of any size. 
Then place the bevel to correspond with the lines A G F. To prove it with 
the dividers or tram, take the distance D E, and sweep to I, on a line from 
B to C. From the point I raise a perpendicular, I K, to the line A D. 
Take the distance K I and sweep to G ; and if the circle I G and the 
line F G meet exactly at the point G, the work is right. (Fig. 346.) 

A Fourth Method. — Let the lines, A, B, C, D, in the diagram represent a 
hopper three feet sqtiare on top and twenty-two mches deep, standing cor- 




FlG. 348. 



nerwise to the reader, and measuring a trifle less than fifty-one inches across 
the top. Now measure distance from centre of hopper to one of the corners 
at right angles with such corner (as shown by dotted line) and lengthen the 
upright line C just so much, as at H ; from which point strike lines E and 
F to the corners of the hopper. Set your bevel by these lines for corner 
pieces, and also for joints of hopper, if square joints, or by one of these lines 
and the upright line H, for mitre joints. (Fig. 347.) 

A Fifth Method. — Let the square, A B D C, represent the top of the hop- 
per ; C D E and C A F the two adjoining sides, of any desired depth. Select 
the points X X at pleasure, equidistant from C, and draw the perpen- 
dicular X Y. Draw the diagonal Y Y, upon which erect the isosceles 
triangle Y Y Z, making the sides Y Z equal to X Y, the angle Y Z Y 
being the angle or bevel sought. To demonstrate : Cut the outline of the 
diagram from a piece of pasteboard ; draw the point of a sharp knife along 



504 MILL WRIGHTING. 

the lines A C and C D ; now fold the two adjoining sides so that the lines 
C F and C E shall join. It will now be seen that the angles Y Y Z and 
Y Y X are equal, Y Y X being the proper angle delineated upon the side of 
the hopper. (Fig. 348.) 

Building an Overshot Wheel. — We will suppose that there is to be 
constructed one of the old-fashioned overshot water-wheels, all of wood, say 
twenty-two feet in diameter and fourteen feet face, for a fall of twenty-four 
feet. This is to be a plain wheel with straight buckets, and built in two 
divisions. The material employed should be white oak, as long seasoned as 
possible, and by natural means, not in a kiln. The shaft must be two feet 
in diameter, sixteen-sided, and, of course, must be dressed from a log more 
than twenty-four inches in diameter at the smallest end. This wheel will 
have arras and segments also of oak ; there will be iron gudgeons or journals 
fastened to the shaft in any one of several manners, we will say by a cap 
fitting over the end of the shaft ; this cap, which will be cast in the same 
piece with the gudgeon pin or journal, will be three feet four inches in 
diameter, and pinned on by square pins. The journals should be as long 
as possible ; we will make them six inches in diameter and at least twelve 
inches long. (Most journals are too short. It must be borne in mind that 
diameter of bearings, while it increases the strength, also causes greater loss 
of power by friction, by reason of the greater leverage that the resistance has 
to overcome. To diminish friction— that is to diminish the loss of power by 
friction — bearings should be as long as possible.) These journals will run 
in cast-iron boxes truly bored out or run with babbitt-metal. For the foun- 
dation and support of the wheel there should be a stone wall, upon the top 
of which are bolted heavy timbers. All the timbers should be air-seasoned, 
i& possible, and the ends should have been painted, to prevent checking 
-or splitting. The log should be felled about the time the sap is running out. 
The small end may be about two feet eight inches in diameter, the large end 
coming, of course, whatever it will be — perhaps three feet one inch for a 
length of twenty-five feet. 

First this round log must be squared up. There must be described upon 
the small end (first squared off) a circle twenty-four inches in diameter, and 
the circumference of this divided into sixteen equal portions by a compass. 
There must be inscribed in it a square, an octagon, and a sixteen-sided 
figure, which will represent the end of the finished shaft and the diagonals of 
these drawn ; then the large end must be marked out in the same manner. 
To do this there must be made two "try-sticks" about three feet long, half 
an inch thick. and two inches wide, perfectly true. To get these perfectly true 
there must really be made three, each of which must be tried with each of the 
other two. By means of these two try-sticks the squares at the two ends of 
the log may be made exactly true with one another, that is, so that each 
angle of one square will exactly cover the angle of the other, and that the 
line drawn from one angle at one end to the corresponding angle at the 
other shall not have any pitch or "wind," but that the plane containing 
them shall be perfectly parallel with the line connecting the two centres of 
circles on the ends of the log. This being settled definitely, the log may be 



BUILDING AN OVERSHOT WHEEL. 505 

roughed out with the common axe, and then more nearly to the outline of 
the sixteen-square with the broad axe, being sure not to cut too close to the 
line, but to leave enough space for finishing, and to guard against mistakes. 
Then, picking out the straightest side, dress off a spot at one end, parallel 
with and forming part of one of the sides of the sixteen-sided figure ; then one 
at the other end of the log, and with the two try-sticks make these perfectly 
true with each other, that is, out of wind, so that the line of sight from the 
two try-sticks placed across these two spots shall perfectly coincide all along 
their length. If these two try spots be perfectly true with each other and 
with the axis of the shaft, there need be little trouble in dressing the other 
sides so as to have them exact. Then the chalk line will be used to lay out 
the lines representing the edges of the faces of the shaft, the stick being 
turned over until all the lines are scribed. It is better to use a straight-edge 
the length of the stick, because with this and the scriber the line can be 
made finer and truer than with the chalk line and chalk or with pencil. 
Having roughed out the sixteen-sided stick true, but not to dimensions or 
perfect in surface, the jack and fore planes may be used to finish. 

The cast-iron caps of the gudgeon should be, say, fifteen inches long, and 
if cast with a round socket the ends of the shaft should be dressed with 
adze and 3-inch chisel to correspond; but it is best to have it cast " sixteen 
square." The chisel employed will be the millwright's chisel, which is very 
heavy and having a very heavy handle. In every other side of the shaft 
there must be holes for the bolts or the wood screws which hold the cap to 
the shaft end. If wood screws are used, they should be ten to twelve inches 
long, and they should be set " staggering," that is, those in one face at one 
end of the cap, those in the next face at the other. The holes for these 
screws must be made with a if-inch auger, so as to give one-eighth of an 
inch draft. This water-wheel will have eight arms at each end, set stagger- 
ing, that is, the arms in one end being in the even sides, those in the other in 
the odd sides. For this size wheel the arms should be 4 x 6 inches in cross 
section at the big end or that next the hub, and tapering one and a half 
inches in ten feet. There should be cast in the gudgeon sockets for these 
arms, or mortises to let them pass through into the shaft mortises. 

In framing a mortise 3x5 inches for the arms (which must have a shoul- 
der), take an inch auger and bore the depth of the mortise across the ends, 
being very careful not to touch the outlines. Of course the face must be 
dressed up first so that it shall be perfectly true, as on this face must 
largely depend the. plumbness or truth of the mortise, and, of course, of the 
arm that it contains. The space between the auger holes must be dressed 
out with a i-g-inch framing chisel. By rights there should be used a corner 
chisel, each face of which is one inch across. (This corner chisel has two 
faces at right angles, and by it it is impossible to make a mortise with any 
acute angles, and almost impossible to make any obtuse angles.) To be sure 
that the mortise is perfectly plumb or true, that its sides are parallel to the 
radius through its centre, the square must be used. To effect this, use the 
square on the sight stick, to get the face at right angles to the radius, and 
then use the small square in the mortise. A 4 x 6 arm might have a half-inch 



506 MILL WEIGHTING. 

shoulder on each side. The arm should be dressed perfectly true before the 
mortise is dressed out. There is no tenon on the other end of the arm, as 
the rim segments are bolted on. The segments of the rim should be of the 
same material as the shaft and arms ; they should be four inches thick by 
twelve inches face, although, perhaps, ten inches would be wide enough. If 
the wheel were twenty-two feet in diameter it would have a circumference of 
about sixty-nine feet, and there would be about thirteen segments. These 
should have a scarf fifteen inches long at each end, the stuff being "halved " 
together and bolted with three -^-inch bolts. The arms should be bolted to 
the inside of the segments with ^-inch bolts. In the centre the arms should 
be a little to one side of the exact centre of the shaft length, in order that 
they might be bolted to the sides of the segments, which should be in the 
centre of the length of the rim. The sheeting should be of i-^-inch plank, 
fastened on with §-inch bolts. 

To frame the rim together after the parts have been worked out, there 
should be made a platform — made by taking a large block out from the end of 
a round log, and about two feet in length, planting it on a level place, and 
running out a spider of eight or ten pieces of common 4x4 stuff, these arms 
reaching as far as the circumference of the wheel would come. Each outer 
end of the arms of the spider should be supported by an upright piece of 
stout common stuff ; and this platform or spider must be perfectly true or 
plane; not necessarily level, but certainly plane. When I said that the end of 
the segments of the rim should be "halved" together, I should have added 
that this is simply a technical expression, for the scarf on the side that is to 
receive the grooves of the buckets must be the thickest, to allow for the 
weakening by cutting. The rim can be laid up true by the use of a sweep 
centred in the centre of the platform. By means of pins placed in holes 
bored in the spider the segments can be all framed exactly true and alike. 
After the frame is dressed true the buckets and "elbows" can be laid out. 
The elbows, running radially, are of 2 -inch stuff, and, say, four inches wide, 
placed one foot apart.* The elbow grooves may be about three-quarters 
of an inch deep, and as wide and long as the elbows are thick and wide ; 
then tlie bucket grooves may be cut out, being laid off on such an angle as 
to let the water run out just before the bucket gets to the lowest point in its 
revolution. The bucket grooves are somewhat narrower at the inner end 
than at the outer, and there should be a strip of just the right taper to allow 
this, say one-sixteenth of an inch in a foot. By the use of this strip the 
buckets may be dressed off at the proper size and taper to fit the grooves. 
The other end of the rim will, of course, have the grooves on the other side, 
or, what is the same thing, running left-handed to those in the first rim. 
The middle arm may be thicker than the end-pieces and be grooved on both 
sides. After the arms are fastened in the shaft, a circle should be swept upon 
them, of the size of the inside of the rim ; then the rim may be bolted on ; 
or the outer ends of the arms may have a shoulder cut down to this circle. 
Of course, before the mortises are laid out in the shaft it must be decided 

* See Chapter on Water- Wheels. 



BUILDING AN OVERSHOT WHEEL. 507 

which way the arms are to be fastened to the rim, so as to allow the proper 
distances between the mortises, etc. After the elbows are in place, the soling 
is put on, this being of edge-beveled strips. Each bucket should be cut to 
length as it is put in, as the rims will warp some. Another way to fasten the 
buckets on is to have the whole wheel covered with a soling, and to bolt to the 
outer edge of the rims triangular pieces two and a half inches thick, and 
of the angle the buckets are to set at ; the buckets to be bolted to these 
angle pieces by two f-inch bolts at each end and two in the middle. The 
buckets should be one and a half inches thick, beveled on the edge next 
the sheathing and square on the outer edge. There are inside segments of 
four inches square, or 4 x 5, to stiffen the* sheathing, half way between the 
ends and the centre segments. To one of the end rims there may be 
bvjlted a cast-iron segmental spur-wheel rim varying in thickness according 
to the power to be transmitted. 



^*^ 



.S3 



CHAPTER XXXIX. 

COMPOSITION AND STRUCTURE OF THE 

WHEAT BERRY. 



[For the preparation of the following very interesting treatise the author 
is indebted to his assistant, Mr. Victor S. Delacroix.] 

A knowledge of the physical formation and chemical composition of 
cereals is the basis of construction of all milling machinery. Knowing that 
which is chemically most valuable, and its position in the grain, we are better 
able to construct machinery which will save and properly treat it, and, at the 
same time, separate and eject all such parts as injure the character and value 
of the desired product. 

In order that our knowledge of cereals may be intimate and complete, it 
is necessary to study them in two ways, chemically and physically. 

By the first method we are able to place a valuation on special elements 
and parts of the grain structure, while by the second may be located these 
more valuable constituents of the cereal. 

Thus, while chemically we may discover which bodies are chemically most 
valuable, it is of the greatest necessity that these valuable parts be localized, 
and hence the necessity of physical study of the grain structure. 

A chemical analysis of wheat shows the following bodies to exist in that 
grain, and detailed analyses of these bodies show them to be composed as 
follows : 

According to Boussingault, the analysis of wheat examined by him was as 
follows : 

Water, . . . . . . . . . . . 14.S3 

Gluten, . ig.64 

* Albumen, . . . .95 

Starch, 45-99 

Gum, . . . _ 1.52 

Sugar, 1.50 

Oil, 87 

Vegetable Fibre, 12.34 

The following-named elements enter into the composition of above speci- 
fied bodies in these proportions : 





Gluten. 
Per Cent. 


Albumen. 
Per Cent. 


Starch. 
Per Cent. 


Gum. 
Per i:ent. 


Sugar. 
Per Cent. 


Vegetable 

Fibre. 
Per Cent. 


Carbon, 

Hydrogen, . 

Nitrogen, 

Oxygen, 

Sulphur, 

Phosphorus, 


53-27 

7-17 

15-94 

23.62 


53-74 

7. II 

15-66 

23-50 


42.80 
6.35 

50.85 


42.68 
6.38 

50.94 


36.1 
7.0 

56.9 


53-23 
7.01 

16.41 
23-35 



COMPOSITION, ETC., OF WHEAT BERRY. 



509 



These constituents named in analysis No. i may be classified according 
to their chemical composition into two classes, nitrogenous and non-nitroge- 
nous bodies. 

The nitrogenous bodies are gluten, albumen and cerealine (not men- 
tioned in the analyses), while the starch, vegetable fibre or cellulose oil, 
gum and sugar represent the non-nitrogenous, or, more properly speaking, the 
carbo-hydrates. All of these are valuable as food, except cellulose, which, 
from its indigestibility, has little value as a food. It would be well, perhaps, 
to casually glance at the chemistry of the nitrogenous elements of the wheat 
berry. 

Wheat, from the large percentage of gluten it contains, is the most valu- 
able of all the cereals, and it may be truthfully said that the amount and 
character of the gluten fix the value of the flour under consideration. 

According to Rittenhausen, gluten is composed of four nitrogenous bodies 
their chemical composition being given in the analysis : 





Mucedin. 


Fibrin. 


Gliadin. 


Casein. 


Carbon, 


54-11 


54-31 


52-67 


52.94 


Hydrogen, 


6. go 


7.18 


7.10 


7.04 


Nitrogen, . 


16.63 


16.89 


18.01 


17.14 


Sulphur, . 


88 


1. 01 


0.85 


0.96 


Oxygen, . 


21.48 


20.61 


21.37 


21.92 



Gliadin, or vegetable glue, is soluble in water, while fibrin, casein and 
mucedin are not. 

It is to mucedin that the characteristic toughness and elasticity of gluten 
is due. 

Fibrin and casein are products readily derived from gluten by treatment 
with alcohol. 

Gluten is easily obtainable by washing flour in a stream of water. If, say, 
an ounce of flour is inclosed in a piece of Swiss muslin or very fine bolting 
cloth, and a stream of water is allowed to run upon it, the mass being 
squeezed while washing, there will be left a grayish mass, of a sticky tena- 
cious character, and which is at first tough and elastic, but becomes brittle 
when dry, and putrifies, under favorable circumstances, like animal tissues. 

If gluten is boiled with alcohol, there will be obtained, first, a grayish 
residue fibrin, and, second, on cooling, a percipitate, which is casein. Fibrin 
represents about 65 or 70 per cent, of gluten"; 

The alcohol may now be boiled to a syrup, and then diluted with water, 
and the gluten (containing probably a little fatty matter) may be recovered. 
The fatty matter may be dissolved out by ether. 

There exists in wheat, besides these, two other protein bodies, albumen 
and cerealine.* The former occurring intermixed with the starch and the 
various juices of the cereal, while, as far as is known, cerealine is located and 
identified with the bran, and is supposed to be a diastasic ferment. 



* Discovered by Mfege Mouries. 



510 



COMPOSITION AND STRUCTURE 



Of the carbo-hydrates (non-nitrogenous elements), starch is the most 
abundant, forming about 45 per cent, of the berry. It is intended as food 
for the germ. There are embodied in every starchy grain certain elements 
necessary to transfer this starch into other products more easily digested; 
these are called diastases, of which maltose and pepsin are familiar examples. 
Most of the starch in the wheat berry is formed in the centre of the grain, 
inclosed in cells of hexagonal shape, with walls of cellulose. The percent- 
ages of starch, as found in the more prominent cereals, is given below: 
Wheat, 49-99 



Rye, 
Corn, . 
Buckwheat, 
Oats, . 
Rice, . 



60.91 
62.05 
65.05 
63.00 
89.1 



Starch (amidon) is identical in composition with cellulose, and supposed 
by some to be a development of vegetable mucus.* It occurs in several forms, 
and of differently shaped and sized granules, usually containing a nucleus or 
hileum. True starch may always be detected by iodine, giving a character- 
istic blue color with that substance. By decomposition, or more properly, 
transposition, it may be changed into glucose or dextrine, etc. It is on 
this principle that the glucose industries are being built up. 

The rotary power of starch is 211°, while dextrine is 176°.! By boiling 
starch with some acids, such as oxalic acid, it may be transposed into dex- 
trine and sugar ; but although this transposition may be easily effected, to 
change inverted starch (glucose) or dextrine back to starch proper has never 
yet been accomplished. 

Starch is insoluble in water, usually, white and glistening in appearance, 
and under the microscope exhibits a characteristic formation and shape 
varying according to the special source from which it was derived. Accord- 
ing to Payen and others it is formed only when nutriment is in excess, and is 
dissolved and used up in a later stage of the cereals ; and although not nutri- 
tious as starch, it becomes eminently so when transposed into dextrine, glu- 
cose, etc., and combined with nitrogenous elements found in all cereals. 

The other carbo-hydrates are dextrine, gum and sugar. As these are 
properly products of transposition, it is doubtful if they exist at all in certain 
stages of the cereal's growth. They are more abundant in flour than in 
wheat, being produced by the process of granulation. Dextrine is repre- 
sented by the brown crust on bread. 

The oil in wheat is localized in greatest quantity in the germ, J which is 

chemically composed of the following elements : 

Starch, 41.22 

Albuminoids 22.66 

Gum and Sugar 9-72 

Fat and Oil, 5.40 

Cellulose, . . . . . . . . . . .5.96 

Ash, 3.99 

Water, . . .11.05 

* Schleider. t Bechamp. 

X It may be readily seen how valuable the germ, from the large percentage of nitrogenous matter 
it contains, would be as a food ; but the discoloration of the flour by the oil renders it hurtful as a con- 
stituent of flour. 



OF THE WHEA T BERR V. 



511 



Now, there remains but to glance at the bran. Having looked at the in- 
side, we will examine the covering. 

Professor Cameron gives the following analyses of the brans of three kinds 
of wheat : Black Sea wheat (from Russia), California and American spring 
wheat : * 





Bran from 


Bran from 


Bran from 


Constituents. 


Black Sea 


California 


American 




Wheat. 


Wheat. 


Spring Wheat. 


Water, . . . 


14-35 


13-05 


14-77 - 


Albuminoids, . 


14-13 


2.36 


16.29 


Oil 


3-77 


4-65 


4-30 


Starch, etc.. 


51-65 


55-21 


47.98 


Woody Fibre, . 


10.50 


11-43 


10.66 


Mineral Matters, 


5.60 


6.30 


6.00 



Wheat Raised in Germany : Chemist Unknown. 



Starch, 

Albuminoids, 
Water, 
Cellulose, . 
Oil, . 
Mineral Ash, 



47.98 
16.29 

14-77 
10.66 

4-30 
6.00 



30.00 
3-50 
3-50 



According to Horsford, the mineral ash of wheat is composed as fol- 
lows : 

Potash, .......... 

Soda, . . . . . . 

Lime, ........... 

Magnesia, . ... . . , . . . . .11.00 

Oxide of Iron, .......... i.oo 

Sulphuric Acid, .......... .50 

Silica, 3.50 

Chloride of Sodium, . . . . ... . . . .50 

Phosphoric Acid, 46.50 

In neither of these analyses is mention made of cerealine, as the presence 
of this body has not been discovered until quite recently. On comparing 
these with other analyses, discrepancies will no doubt be discovered ; but 
these are due to the analyses being either for different varieties of grain or 





Fig. 349. — Wheat, Natural Condition, 
Highly Magnified. 



Fig. 350. — Showing Grain after having 

PASSED THROUGH A BrUSH MACHINE. 



from the special method of analysis used by the chemist. They have been 
selected as made by standard authorities, and we believe that they are ap- 
proximately correct. 

We now come to the physical examination of the wheat structure. 



* American Miller. 



512 



COMPOSI TION AND S TR UCTURE 



Fig. 349 represents a grain of wheat in its natural state, while Fig. 350 
shows a portion of the same after having passed through a smutter, and as 
it appears without its silicious coat. It will be noticed that on the end of 
the berry (Fig. 349) there is a fuzz or " beard," made up of hair-like bodies, 
of cellulose. 




Fig. 351.— Hairs or Beard of Wheat Berry Highly Magnified. 



Fig. 351 shows the hairs at the end of the berry, greatly magnified. 
These hairs are composed of a single cell, with very thin cell-walls inserted 
in the outer covering of the wheat, penetrating the cellular tissue, as shown 
by the figure. 




Fig. 352. — Cross Section of Wheat. 



The envelopes inclosing the starchy centre of the wheat berry may be 
roughly computed as consisting of six coats. These are formulated in 
" Cerealia" * as follows : 



* A very interesting and quite complete little pamphlet by Mr. Jno. D. Nolan. We would here 
acknowledge the use of some cuts from the same work. 



OF THE WHEA T BERR Y. 513 

Fruit Coats. 

1. The epicarp, or outer coat of longitudinal cells. 

2. The mesocarp, or inner coat of longitudinal cells. 

3. The endocarp, or coat of transverse cells — the cigar coat. 

Seed Coats. 

4. Episperm testa, or outer seed coat. 

5. Tegumen, inner seed coat, or gluten comb coat. 

6. Layer of gluten sacs. 

Fig. 352 represents a cross section of wheat, magnified 225 times. The 
inner ring of irregular black dots is supposed to represent the gluten. The 
inner portion is made up of starch, inclosed in hexagonal cells. It also 
shows the crease, which gives the miller so much trouble from retaining dirt 
and foreign matter, which discolors the flour. 

Fig. 353, on following page, represents a longitudinal section of a grain 
of wheat made by Mege Mouries, and the various tissues are numbered as 
follows : 

1. Outer or first coat. 

2. Epicarp, or outer coat of longitudinal cells. 

3. Mesocar longitudinal cells, but with the greatest length of cell running 

perpendicular to those of the outer coat. 

4. Endocarp, or inner fruit coat of transverse cells. 

5. Episperm, testa, or outer seed coat. 

6. Embryo membrane, or expansion of germ. 

7. 8 and g. Gluten cells containing starch. 
10. The germ. 

The first three coats are fruit coats, consisting of woody fibre, similar in 
composition to straw. They are easily separated from the wheat.* But we 
will consider their construction more in detail farther on. 

Nos. 4, 5, 6 are the membranes causing so much trouble in flouring. 

The external testa, or episperm No. 5, contains the coloring matter, usually 
light yellow and orange yellow. The intensity and predominance of one of 
these colors gives the wheat its name, white, amber, reddish or red, as the 
case may be. It represents less than 2 per cent, of the berry. 

No. 6 is that portion of the berry which produces the best flour, being 
harder and richer in gluten. This, mixed with equal parts from the centre, 
produces the finest white flour. 

No. 7 is still richer in gluten. 

Nos. 8 and 9 mixed together form a high grade flour of good color, and 
one hundred parts of this flour would produce one hundred and thirty-seven 
parts of bread. 

Fig. 354 is the first coat or epicarp, very highly magnified. It is composed 
of irregular longitudinal cells with the thick walls, very common to epithelial 
structures. The greatest length of the cells corresponds with the longitudi- 
nal section of the grain. 

Fig- 355 represents a section of the inner fruit coat, endocarp, or coat of 
transverse cells, sometimes called the cigar coat. These cells run with their 

* These tissues represent about 3 per cent, of the berry. 



514 



COMPOSITION AND STRUCTURE 




f"'G- 353-— Longitudinal Section of Wheat, with Imaginary White Spaces, to render 

Tissues more Prominent. 



OF THE WHEAT BERRY. 



515 



greatest length perpendicular to the outer coat or with the smallest section 
of the berry. 





Fig. 354. — Epicarp. Fig. 355.— Endocarp. 

The cellular structure of the central portion of the wheat berry is very 
nicely shown by Fig. 356. 




Fig. 356. — Cells from Centres of Wheat Grain, a Filled with Starch. 

The cell walls are composed of laminated cellular tissue of extreme deli- 
cacy. The central portion, No. 9, contains the cells most heavily loaded 




Fig. 357. — DiEHL Wheat Starch. 

with starch, and yielding a beautifully white flour of little consistency, and 
incapable of making light digestible bread. 



516 



COMPOSITION AND STRUCTURE 



Fig. 357 represents starch from Diehl wheat. The smaller grains are prin- 
cipally composed of broken portions of gluten and other nitrogenous matter. 
Fig. 358 is starch grain of Clawson wheat, highly magnified. This is 



Oo 



VcJ Yo 




o o 



00 



00 



00^ o "^.^ 



°.° ° °0° »3?^' ° C 



i0<? 



O 







o 



"6 



Fig. 358. — Clawson Wheat Starch. 



the richest in starch of any wheat grown. It yields plentiful crops, and gives 
a beautifully white floor of little body. 




Fig. 359. — Outer Layer of Nitrogenous Elements. 

Fig. 359 corresponds in section to seven of the larger cut. It is that 
portion of the berry containing the greatest amount of gluten. Being imme- 




Fig. 360. 



diately next the tegumen, or inner seed coat, and as its separation from this 
coat is difficult, it produces a dark flour very rich in gluten. 

Fig. 360 is another part section of wheat, showing the fruit and seed 
coats and gluten grains more highly magnified. 



OF THE WHEAT BERRY. 517 

The art of milling is to manipulate the grain so as to obtain the greatest 
percentage of most valuable material. 

A glance at the chemical composition of bran will show at once its unfit- 
ness as a food, consisting of from lo to 12 per cent, of woody fibre, which is 
totally indigestible. It should, therefore, be rejected as useless as a nutri- 
tive product of flour, being not only worthless as a food, but injuring the 
market value of product by discoloration. The germ, though very nutritious 
in character, has to be rejected also for the latter cause, as well as by reason 
of the oil it contains causing rancidity from oxidation. 

The " strongest " flour is a dark flour, and hence less valuable from a 
money point of view. 

Wheat of the same variety from which section Fig. 353 was made, yielded 
these results when floured : 

Gluten and Produces Bread. 

100 parts of flour in centre contain 8 " 128 parts, 

first layer " 9.2 " 136 " 

" " second layer " 11 " 140 " 

" " external layer " 13 " 145 " 

The flour from the external layer is so dark as to make a brownish bread, 
and is, hence, less sought for and less valuable commercially. It would 
seem that the lines of advancement in milling would be those of granulation, 
bran cleaning and wheat meal purification before bolting, especially the 
latter, and by methods depending on other qualities than size, as in grinding 
the bran is reduced as fine as the flour, and separation by size is therefore 
an impossibility. 

Many valuable improvements in milling machinery have been made dur- 
ing the past few years, and it is to be hoped that the next decade will see a 
corresponding advancement. 



^';i!^ 



CHAPTER XL. 

GRAIN DESTROYERS. 

Vegetable Organisms — Weevils — Rats. 

All kinds of grain are preyed upon by living organisms of animal or vege- 
table origin. From the time it is sown in the ground to its storing in the 
granary it is the accepted food of myriads of hungry organisms, some attack- 
ing it in one stage of its growth and some in another. For convenience, the 
parasites which ravage our crops may be divided into two classes, vegetable 
and animal, and a casual glance at the most prominent and rapacious will 
probably not be amiss. 

Vegetable Organisms. — Of those of vegetable origin, the following 
are the most common in the work of destruction : Smut, rust and brand, 
mildew and ergot. These vegetable organisms are parasitic fungi which 
live upon the juices of the plant and work destruction either directly in the 
grain itself, as wheat smut, or destroy the vitality of the plant, as rust, 
brands, etc. These plants multiply and reproduce themselves not by means 
of pollen, as is the case with many plants, but by spores, the fructification of 
which produces sad havoc. Smuts are parasitic fungi, the filaments of which 
grow through the cell walls of the plant, absorbing its juices and tissues. 
The ends of these filaments become articulated into cells developing into 
spores. These spores form the brownish black powder observed on the 
wheat and oats. 

The sporules of wheat smut or bunt {Tilletia caries) fructify within the 
berry itself. On pressing a grain of wheat affected by smut, it bursts with 
slight pressure, and is found to be filled with a blackish powder emitting a 
nauseous odor of trimethylamine, a volatile oil which is also found in her- 
rings. There are several other varieties of this parasite, as oat smut ( Us- 
tilago carbo), which affects the panicle or raceme of oats ; and corn (maize) 
smut {Ustilago maydts), affecting the female corn cob. 

Rust and brands are parasites which, instead of working destruction 
directly in the grain itself, destroy the leaves, infecting them with reddish 
pustules or cup-like protuberances. If a field of infected grain be examined, 
on the under side of the leaves will be noticed these reddish pustules or cups, 
which developing, the germ tubes force their way through the epidermis 
and branch out filaments on the inside of the leaves which articulate into 
cells producing sporules. These cluster cups are often found on other 
plants, and the spores from them on coming in contact with the cereals will 
at once commence to germinate. The cluster cups of the barberry produce 
spores which cause a very dangerous form of rust ( Uredo linearis), while the 



WEEVILS. 519 

well-known rust ( Uredo rubigo) of the cereals has its origin in cluster cups 
growing on other plants in the neighboring fields. That the diseases of 
wheat known as rust and brands were produced by sporules from parasites 
growing on other plants in the neighborhood of the fields has been proved 
beyond the shadow of a doubt by Professor De Bary, of Strasburg. Mildew 
{Eurisiple graminis) is a parasitic fungus feeding on the juices of the plant 
and impairing its growth. The appearance is that of a white fuzz. Other 
varieties of mildew are very destructive to fruit trees. 

One of the most peculiar and dangerous diseases to which cereals are 
exposed is the ergot. Tulsane was the first to show the immediate connec- 
tion which existed between the different stages of development of this 
peculiar disease. The mucous, honey-like substance called honey dew by 
the farmers is the second stage of development. If this honey dew is highly 
magnified it will be found to be swarming with sporules. These spores are 
found to issue from a slender mycelium or filament which afterward hardens 
and becomes the ergot grain. This develops the next spring into the third 
condition, or Claviceps purpurea, which causes fatal poisoning. The Ger- 
man name of the ergot is mutterkorn, from its causing contraction of the 
uterus. In 1771, whole villages in Westphalia and Hanover were poisoned 
and in certain villages over 90 per cent, of the cases proved fatal. Ergot is 
now largely used in obstetrics, and is known in this connection as Secole cor- 
mctuj/i. 

Weevils. — The weevils which give the most trouble are probably the 
grain weevil, Calandra granaria, and the rice or black weevil, Calandra 
oryzcB. 

The grain weevil is a reddish little beetle, with a long nose or snout, sur- 
mounted with two club-like antenna, or feelers. In the earliest stages of de- 
velopment it is destitute of wings, but the fully grown insects are found to 
possess them. The body is elliptical in shape, and the whole insect a little 
less than one-third the length the longest diameter of a wheat berry. 

The rice weevil is a native of the East Indies, and was imported into the 
United States by trading vessels from Eastern ports. It is of a black color 
and a little less than one-eighth of an inch in length ; the snout is about one- 
thirty-second of an inch long, or one-fourth the length of the body. The 
elytra are black, with four orange spots. 

The female weevil lays a prodigious number of eggs, not in a mass, but 
one at a time. She first carefully drills a hole in the berry and lays a single 
egg in the cavity thus formed, the opening of which is plastered up with a 
glutinous secretion. It requires about fifty days for this egg to develop into 
a perfect insect. A few days after the egg is laid it hatches into a white 
grub, which immediately commences devouring the starchy and glutenous 
portions of the grain surrounding it. After it has eaten all but the woody 
fibre or covering of the berry, it goes into a second state and becomes a 
chrysalis, as which it remains about two weeks, when it is metamorphosed 
into a perfect insect. 

As it does not disturb the outer covering, it is very difficult to tell 
damaged grain. If, however, the suspected grain be put in water, the good 



520 GRAIN DESTROYERS. 

berries will sink, while the shells containing the grub will, from their lightness, 
float on the surface. 

There have been numerous recipes offered for the destruction or preven- 
tion of the depredations of weevils, the principal of which are : Kiln dry- 
ing, sulphur fumes, sprinkling air-slacked lime among the grain. Insect pow- 
der, tarred paper, and various other remedies have been suggested. It has 
been proved that the weevil cannot stand a high degree of heat, and grain 
heating has been resorted to to kill the eggs and grubs. Weevils cannot live 
and breed without moisture ; if the grain is kept thoroughly clean and dry 
it is generally safe from the attacks of these pests. 

" The America?! Agriculturist says that barn weevils are not brought in the 
granary in the wheat, but attack the grain only after it is harvested. The 
granary should have no crevices to harbor or admit the insect, and all ven- 
tilation spaces should be covered with fine wire gauze. In France the recep- 
tacles are often built of sheet iron." 

Fyrethrum roseu7?t, or Persian insect powder, is said to drive away 
weevils. 

"It is said that a bag of hops in each bin will keep grubs or weevils out, 
or kill them if already in. Aniseed also attracts and kills weevils and pre- 
vents their harboring." 

"The grain bins, if of wood, should be whitewashed. Weevils hate any- 
thing that is clean. One man says that if all else fails put a tarred board in 
the bin where the weevils are and they will leave on short notice. " 

"Gum camphor is used, tied in a rag, as a protection against mill bugs." 

Rats. — The ravages caused by rats have long been an eyesore and a loss 
to millers and others. The amount of damage inflicted by them can safely 
be estimated as amounting to millions of dollars yearly. In the mill, not 
satisfied with grain destruction, they sometimes attack bolts, screens, sacks, 
etc., doing in a single night damage requiring days to repair. 

Various systematic methods, in the form of traps, poisons, etc., are prac- 
tised in the hope of increasing the mortality of these pernicious rodents. 

Among other methods on record for clearing a building of these pests is 
one, quite unique in its way, by suffocating them with chlorine gas. 

The methods applicable are of a character not allowing free ventilation, 
as free ventilation allows the gas to escape or mix with so great a quantity 
of air as to impair its efficiency as a destructive agent. 

First plaster up all the holes but one. By pouring greatly moistened 
chloride of lime down the burrow and following it with diluted muriatic 
or oxalic acid, chlorine is profusely generated. If how the remaining outlet 
is closed, the rats are " gone coons." 

The same plan can be pursued where rats are between the floors, first 
nailing up the outlet with sheet iron and proceeding to suffocate in the usual 
manner. It is said by those who have tried this method that they have been 
able to free their buildings entirely. 

It is stated that premises may be cleared of rats by making lime wash yel- 
low with copperas and covering the stones and rafters in the cellar with it, 
and also scattering copperas liberally about. 



CHAPTER XLI. 



MISCELLANEOUS. 

Helps to the Miller— Duty — Ordering Machinery — Choice of Stone — Straightening Shafts — Cost 
and Depreciation of Machinery — Cost of Manufacture — Qualities of Wheat — Cost of Wheat 
Transportation — Prices of Wheat — Calculations — Problems and Solutions. 

Helps to the Miller. — There are plenty of things that many people 
know, but which they either forget or underrate, hence there is some use in 
calling their attention to them once in a while. If more men kept note-books 
than now do, there would be fewer things let go by which ought to be remem- 
bered. Very often a miller hears or remembers something which he knows 
will be of use to him in his business ; but he lets it go so long that, when 
the time comes in which it would be of use to him, it is not at hand. It is a 
very good plan to keep scrap and note books. The scrap-book and the note- 
book are great helps to the pocket-book and the bank-book. 

Duty. — In the mill let each man have a definite part to perform. If the 
mill is run on two spells, day and night, let the night miller come in at 5.55 
p. M. The day miller, having looked all over the mill, gives the night miller 
his suggestions or instructions. The night hands should not be allowed to 
leave the mill while on duty, nor to go to sleep under any consideration. If 
the miller is allowed to serve as general roustabout, he will, in greater or less 
degree, lose his fine sense of touch. 

Ordering Machinery. — In ordering any kind of special machinery, 
to do almost any kind of work, it is desirable to have the machines of the 
best design and make ; for, while inferior machines may do work that will 
pass, or even do good work for a while, there is sooner or later a time when 
the poor machine gives out, even if it does good work at first ; and to merely 
be able to do work that will sell or that will surpass former achievements, 
is not enough. It is proper to get the best machine, the best work and the 
greatest durability. There is more reason for a miller to expect to get good 
work out of poor rolls, than that they should expect to get work out of burrs 
of poor stock, badly selected, badly built, badly mounted, badly dressed and 
run at the wrong speed. 

Choice of Stone. — Kick says that for clean, dry, hard wheat, the stone 
should be close, hard and tough. Pieces of flint prevent the burr from tak- 
ing a proper dress. For soft wheat of a yellow color, with fine bran, and 
mealy moist interior, should have a porous stone, tough and sharp. Ordi- 
narily, such wheat grinds tough. The chop or breaks feel soft. The stone 
must have more pores and be sharp. 



522 MISCELLANEOUS. 

Straightening Shafts. — To straighten a wooden shaft, take hard 
seasoned lumber and dovetail it into the shaft at the crookedest part. To 
straighten an iron shaft, fix three or five pieces of iron or stone, so that fire 
will not affect them, and so that their upper surface will be in exact line. 
Fix the shaft firmly upon them, with the bend up. Build a fire under .the 
shaft and heat it evenly the entire length, when it can be bent down to the 
straight line of the supports. Do not heat hot enough to cast a scale. 
Another way is to support the shaft at the ends, let the bend hang down, 
fasten the ends tightly, and while forcing the bend upward from below with 
a lever, pene the upper surface with a hammer, so as to stretch or lengthen 
it. This bent surface must never be turned off, as the shaft would crook 
again. 

Cost and Depreciation of Machinery. — " Best French burrs, 30- 
inch, cost §175 ; for every additional inch add S6. This is for stones simply 
faced ; if furrowed add 15 per cent. Curb and feeder, $25, setting $25, 
depreciation 20 per cent, in twenty-five years. Refilling spur wheels once in 
six or eight years, $100 to $150. Bolting chests, 16 feet, with 40-incli reel, 
$360, 20-foot chest $540 (one 12-foot elevator included). Two to four reel 
chests, including cloths, shafting and gearing, $1,500. Iron bolting reel, S40 
to S50. Bolting cloth, Si. 25 to $3.50 per yard ; making up, 35c. per yard. 
A forty-inch reel takes one yard of cloth for each foot of reel length. De- 
preciation of cloth, 25 per cent, to 33 per cent, per year ; in an old mill 
more than this, by reason of bugs. Annual depreciation of the rest of the 
chest, 3 per cent. Middlings purifiers, I275 for one pair of burrs, $100 ad- 
ditional for every extra pair ; average life of a purifier in a merchant mill, 
eight years. Smutter of ten to fifteen bushels per hour, liio ; 125 bushels, 
$250 ; life in custom mills, twenty years ; in merchant mills, ten years. A 
smutter can be recased for I15 or $20, and be as good as new. Elevator 
buckets, 15 to 50 cents each ; elevator boot and pulley, $12 ; rivets, $1.50 
per hundred ; fastening cups to belts, 2 cents each. The principal wear in 
elevators is that of the cups. In a merchant mill the leather pulley lasts ten 
to twelve years, the cups six months to two years. Annual depreciation of 
slow geared machinery, 5 per cent.; of fast geared, 20 per cent." 

Cost of Manufacture. — It is strange how few millers know just how 
much money it costs to make a barrel of flour ; and when it comes to being 
able to say just how many cents it costs for each item, power, wages, inter- 
est, rent, repairs, insurance, etc., there are fewer still who can tell anything 
about it. We have taken a great deal of trouble and gone to a considerable 
expense to get from different millers their statements of these items, and 
while they differ widely, they do not differ any more than the systems of 
milling. We give, on following page, a statement of cost from an Ohio new 
process burr mill, running through five years : 

The separate accounts will explain themselves in part. It should be 
added, however, that as the mill is owned by those running it, no direct 
account of rent is shown. The taxes come under the head of '' expense ; " 
current repairs come under that head, but permanent additional value is not 
shown. The wages cover office services, but nothing charged in the way of 



MISCELLANEO US. 



523 






X 

o 
z 



> 

u 
z 






CO 



en 

< 
W 
>- 

W 
> 



O 
<A 
O 

O 

z 

s 

H 
O 

< 

Z 
< 

ti 

O 

a 
(f) 
z 
w 

Oh 





c^ 


in 


CO 











IH 


qj 





en 








r^ 





CO 




6 





CJ 


m 


CO 


ON 


in 


a^ 


in 


M 








CJ 


-r 


i: 


r^ 





in 


CJ 


m 


r^ 


ON 


he 
bj3 
















IN 


(N 


i_i 





CJ 


On 


M 


< 




M 








m 




& 










€«■ 


m 




d 


cn 


r^ 


CO 


m 


1~( 







00 


in 





<y- 


vO 





■* 


'5 


CO 





00 


CO 


ON 


cJ 





a 


vO 


00 


00 




ON 


m 


t^ 


u 


01 


in 


M 


t^ 


m 


CO 


00 


C«i 


^ 




M 








^ 


aj 


-* 


CO 







M 


ON 







vr^ 


CJ 


^ 


CJ 


0^ 


CJ 


NO 


rt 


d 


CJ 


CO 





N 


CO 


d 


3 


CJ 


r^ 


l-H 





00 





CJ 


w 


00 


CO 


r^ 


r-^ 


ON 


HH 


00 


C! 


m 










i 


^ 




\-i 


tn 


M 


CJ 


■* 


M 







<Xi 


ON 


m 


t^ 


in 


in 


ON 


V) 

o 


4 





00 


(^ 


On 


0- 


m 


bjo 


00 


■* 


■a- 


CJ 





i^ 


■M 


ci 


c*^ 


r^ 


-:)■ 


CJ 


CJ 





•*; 


^ 
















Tf 


-* 


^ 


■* 


Tf 


CJ 


^ 




^ 












m 


■T3 





CJ 


a^ 


r^ 


r^ 


•* 


t^ 


S -" 





in 




* 





CO 


00 


" C 
















■u 3 


r^ 


a> 


Ti- 


CJ 


lO 


S" 


l-t 


M O 


O^ 


en 


■* 


00 


^ 





00 


In "5 


a> 


r^ 


r^ 


CO 


o_ 


■* 


•* 
















1° 


^ 


en 


CJ 


Cj" 


CO 


r^ 


CO 


m 










^ 


«© 







•* 


in 


•* 


CJ 


1-4 


CO 


<u 4J 







r^ 


r^ 


10 





ON 


S c 
















c 3 


^ 


M 


CO 


ON 


in 


^ 


NO 


0) 


w 






CJ 





CO 


in 


a. 


rn 


r^ 


TT 


r^ 


<l 


t^ 


CO 


X 
















W < 


ff 


Cj' 


Cj' 


>-• 


cT 


M 


Cj" 


^ 












m 






r^ 





CJ 


00 


in 







•d 


in 


CJ 


CO 






CJ 


'a- 


c 


















3 


















. 




































1 


















J3 *j 


tn 


t^ 


CJ 


r^ 


r- 


CO 


CO 





^ § 







1- 


m 


r^ 


CJ 





<* 


j3 





r^ 


in 


r^ 


NO 


r- 


w 




a 
















CO 


n. 


CO 


CO 


r-. 





m 


w 


3 


■* 


CO 


CO 




CJ 





CJ 


< 


S3 


M 






M 




lO 




d 


• 




• 




• 


r 




r^ 




• 








' 





















C 


. 








• 




• 


3 
















>— . 











































• 






» 












, 




^ 

































3 












c« 


U 


»-» 












bo 


bo 


S 












o 


C3 












Li 


u 















ho 


<D 


^ 





f- 


CO 








bO 
< 


> 


Ii. 


1 


1 


1 


1 


1 


<; 




\n 





t-« 


CO 


On 








r^ 


r^ 


r^ 


t^ 


r^ 








CO 


00 


00 


CO 

M 


CO 







ON 
CO 



O 

o 






o 



o 

CO 






c« 








-1 








XI 


* 












>^ 




c 




^ 









■a 




bo 


7 


(U 


• 


c 


<u 


L« 














u 


rt 




3 


rt 







u 


J3 


OJ 




,« 


M 







3 
C 




c 






ri 


^^ 




\-, 


0) 




c/^ 


3 


t-l 


b 


C 




is 


. 


0) 


J3 


,p 





1 


!-• 






ca 


<u 






C 


p. 














0) 

bo 


rt- 


-5 





tfl 


c« 


U 










> 


0) 


in 




< 


a: 





34 



524 MISCELLANEOUS. 

partners' wages. Insurance covers as heavy a line as prudence dictates, but 
it necessarily leaves a risk to be carried by the owners. The mill is driven 
by water, and maintenance of power is covered in the above. 

The Jones single roller machines have not been long used for the entire 
reduction of wheat to flour, but after making the middlings on millstones 
they were ground on the single rolls. The cost of manufacture for a run of 
11,568 barrels is given by Mr. James Jones, as follows : 

Insurance, \\ cents.; coal, 8f cents ; labor, lof cents, with incidentals 
only a fraction of a cent. Total for these items, only about 2\\ cents. Of 
course, in these figures, the important items of repair, rent, interest and dis- 
count and general expense account are omitted. 

Qualities of Wheat. — Millers and grain dealers should impress upon 
the farmer the importance of improving the quality of his wheat, by taking 
the best seed each year, so as to get the earliest possible maturity, the largest 
grass and the best growth. 

Black Sea wheat is thin and brittle, and lacks fibre. 

Wheat grown in some years is harder and has thicker bran than that of 
other years. 

The Michican winter wheat is about the softest that the miller gets. 
In the Pacific wheat there are some things that specially annoy those in 
charge of the cleaning. California wheat is soft in the northern portion, the 
Russian River districts, Sonoma and Napa valleys, etc. In the San Joaquin 
and Clara valleys the wheat is dry and hard ; along the coast line it is moist. 
It is said to gain enough in weight in the passage across the ocean to pay for 
the freight. 

There is a great deal of Oregon wheat that is shipped down to 
California and passes for California wheat, very much to the disadvantage 
of the latter, because the Oregon wheat is weak, like Michigan white 
winter. 

For burr mills, or, in fact, for any kind of milling, the red winter Medi- 
terranean is by far preferable. The kinds that are generally the most trouble- 
some in the burrs are Clawson wheat and similar varieties. Yet Clawson 
seems to do better in New York State, where millers do not find any fault 
with it. 

Good Mediterranean" and Russian seed are best for fall planting, give 
good yields, please the millers and the bakers. 

Red wheat is stronger than white ; the grain is usually small and 
hard. The large white grain is peculiarly adapted to making fine white 
flour. 

In practice, 100 pounds of flour make 133 to 136 pounds of 
bread. 

Southern wheat makes more bread than Northern, because, in ripening, 
there is more evaporation, and the farina being left in a more condensed 
state will, when made into dough, absorb a larger quantity of water. Ameri- 
can wheat is said to absorb 10 to 12 per cent, more water than European. 
Whereas five bushels of wheat was considered necessary some years ago in 
the Northern States to make a barrel of flour, now four and a quarter to four 



MISCELLANEOUS. 525 

and a half are enough. There is a barrel of excellent superfine flour in 210 
pounds of good dried wheat, weighing sixty pounds to the bushel. This 
shows that there is a loss of nearly a bushel of wheat to each barrel of super- 
fine flour, this loss being mainly from the best and most nutritive part of the 
grain — the gluten. This is due to imperfect preparation more than to the 
machinery. It is gluten which determines the real value of wheat flour. The 
bran of dry wheat is so brittle that it is apt to cut up fine, speck the flour 
and discolor it. To avoid this, many millers set the stones apart and dress 
them, so as to partly grind or break open the wheat and get out the white 
starch of the flour, and then, in an after grinding, the gluten and the bran go 
in what will be sold as a lower grade of flour on account of its color, though 
really it contains the most valuable constituents of the grain, and is a more 
valuable and nourishing flour. 

Millers mix soft or dry wheat to a good average, and sprinkle water 
on the very dry wheat before grinding. Now, dry wheat contains on 
the inside about 8 per cent, of water, part of which renders it suffi- 
ciently tough, if ground at a temperature of 100° Fahrenheit, to be worked 
easily. 

Cost ofWlieat Transportation. — In a pamphlet addressed to the 
" Western Farmers of America," lately issued by the Cobden Club of Eng- 
land, by Augustus Mongredier, we are assured that we are paying a grievous 
tax in the way of railway transportation of our crops, in consequence of the 
heavy cost of rails used in the construction of our roads. To show the 
absurdity of this assumption it is only necessary to look at the price of 
freight on wheat from Chicago to New York for a series of years. 

At the close of the war the price of transporting a bushel of wheat 
between the above points was sixty-four cents. The reduction from 
that to fifteen cents, the present price, is shown by the following 
figures from the report of the United States Bureau of Statistics, 
for 1879, to bear no relation to the fluctuation in the price of rail- 
road iron. 

32 cents. 

28 " 
24 " 

16 " 

20 " 

. .... 17 " 

It is doubtful if grain can be carried on English railroads with their low- 
priced rails or cheap labor. The strong competition between the several 
railroad lines, and between these and lake transportation, gives the grain 
producers of the west very low through rates. But it is hard to please our 
English neighbors while we make our own railroad iron instead of buying 
Welsh rails. 

Underneath the reader will find a tabulated summary of the average 
shipping freights which have been paid on wheat and corn during the ten 



1873, 


average per bus 


1874, 




1875, 




1876, 




1877. 




1878, 





526 



MISCELLANEO US. 



years ended 1880, from Chicago to Buffalo, and from Buffalo (by way of 
the Erie canal) to New York: 





Lake. 


Canal. 


Year 












Wheat. 


Corn. 


Wheat. 


Corn. 


1870 . 


5.0c. 


4.7c. 


9.4c. 


9.2c. 


1871 


6.2 


5-7 


11.8 


10.8 


1872 . 


9.6 


8.8 


12.0 


10. 


1873 


6.5 


5.6 


10.06 


9.6 


1874 ■ 


3-1 


2.0 


9.0 


8.0 


1875 


2.8 


2.6 


7-5 


6.9 


1876 . 


1.6 


r.i 


5-9 


5-4 


1877 


2.6 


2.2 


5-4 


4-7 


1878 . 


1-7 


1-5 


4.3 


3-8 


1879 


2.5 


2.3 


5-2 


4-7 


1880 . 


4.8 


4-3 


6.0 


5-1 



Calculations, — A two-foot rule was given to a laborer in a Clyde boat- 
yard to measure an iron plate. The lumper, not being well up to the use of 
the rule, after spending a considerable time returned. " Noo, Mick," asked 
the plater, "what size is the plate ?" "Well," replied Mick, with a grin of 
satisfaction, " it's the length of your rule, and two thumbs over, with this 
piece of brick and the breadth of my hand, and my arm from here to there, 
bar a finger." 

To find the capacity of a hopper, multiply the length by the breadth, and 
this product by one-third of the depth, measuring to the point (in inches), 
and divide the last product by 2,150, the number of cubic inches in a 
bushel. 

The length of belting in coils may be found by taking half the sum of the 
diameters of the inner and outer coils, multiplying the number by 3.1416 and 
the product by the number of coils. If the diameter of the coils be taken in 
inches, this will give the length of the coil in inches. 

For diameter in centimetres to circumference in metres, diameter multi- 
plied by .0314. 

For circumference of a circle, diameter multiplied by 3.1416. 

For getting circumference in feet from diameter in inches, diameter in 

inches multiplied by ^^^^ = .2633. 

To get circumference in feet from diameter in centimetres, multiply the 
diameter m centimetres by ^^ = 103. 

Prices of Wheat. — As a ready reference for the purpose of calcu- 
lating the price of wheat, the tables on the succeeding pages will be found 
very useful. 



MISCELLANEO US. 
Calculations as to Prices of Wheat. 



527 







76. 




80. 




8S. 


Pounds. 


Bushels 




Bushels 




Bushels. 






^j \^^t.i. \^ L^jt 


Dolls. 


Cents. 


JL-^ \^iJ^X\jU9 


DoUs. 


Cents. 




Dolls. 


Cents. 


60 


I 


.76 


I 


.80 


I 


•85 


. 120 


2 


1.52 


2 


I .60 


2 


1.70 


180 


3 


2.28 


3 


2.40 


3 


2-55 


240 


4 


3-04 


4 


3.20 


4 


3-4° 


300 


5 


3.80 


5 


4.00 


5 


4-25 


360 


6 


4-56 


6 


4.80 


6 


5.10 


420 


7 


5-32 


7 


5.60 


7 


5-95 


480 


8 


6.08 


8 


6.40 


8 


6.80 


540 


9 


6.84 


9 


7 . 20 


9 


7-65 


600 


10 


7.60 


10 


8.00 


10 


8.50 


660 


II 


8.36 


II 


8.80 


II 


9-35 


720 


12 


9.12 


12 


9.60 


12 


10.20 


780 


13 


9.88 


13 


10.40 


13 


11.05 


840 


14 


10.64 


14 


II .20 


14 


II .90 


900 


15 


II .40 


15 


12 .00 


15 


12.75 


960 


16 


12.16 


16 


12.80 


16 


13.60 


1020 


17 


12 .92 


17 


13.60 


17 


14-45 


1080 


18 


13.68 


18 


14.40 


18 


15-30 


1 1 40 


19 


14.44 


19 


15.20 


19 


16. 15 


1200 


20 


15 . 20 


20 


16.00 


20 


17 .00 


1260 


21 


15-96 


21 


16.80 


21 


17-85 


1320 


22 


16.72 


22 


17.60 


22 


18.70 


1380 


23 


17.48 


23 


18.40 


23 


19-55 


1440 


24 


18.24 


24 


19.20 


24 


20.40 


1500 


25 


19. GO 


25 


20.00 


25 


21 . 25 


1560 


26 


19.76 


26 


20.80 


26 


22 . 10 


1620 


27 


20.52 


27 


21 .60 


27 


22.95 


1680 


28 


21.28 


28 


22.40 


28 


23.80 


1740 


29 


22 .04 


29 


23.20 


29 


24.65 


1800 


30 


22.80 


30 


24.00 


30 


25-50 


i860 


31 


23-56 


31 


24.80 


31 


26.35 


1920 


32 


24.32 


32 


25 .60 


32 


27 .20 


1980 


ZZ 


25.08 


33 


26.40 


33 


28.05 


2040 


34 


25.84 


34 


27. 20 


34 


28.90 


2100 


35 


26.60 


35 


28.00 


35 


29-75 


2160 


36 


27.36 


36 


28.80 


36 


30.60 


2220 


37 


28.12 


37 


29.60 


37 


31-45 


2280 


38 


28.88 


38 


30.40 


38 


32-30 


2340 


39 


29.64 


39 


31.20 


39 


33-15 


2400 


40 


30.40 


40 


32.00 


40 


34.00 


2460 


41 


31.16 


41 


32.80 


41 


34-85 


2520 


42 


31.92 


42 


33 60 


42 


35-70 


2580 


43 


32.68 


43 


34-40 


43 


36.55 


2640 


44 


33-44 


44 


35 -20 


44 


37 40 


2700 


45 


34.20 


45 


36.00 


45 


38.25 


2760 


46 


34-96 


46 


36.80 


46 


39.10 


2820 


47 


35-72 


47 


37.60 


47 


39-95 


2880 


48 


36.48 


48 


38.40 


48 


40.80 


2940 


49 


37-24 


49 


39.20 


49 


41.65 


3000 


50 


38.00 


50 


40.00 


50 


42.50 



528 MISCELLANEOUS. 

Calculations as to Prices of Wheat. — Continued. 







90. 




95. 




1.00. 


Pounds. 


Bushels 




Bushels 




Bushels 






VJ hA ftA V« X hj • 


Dolls. 


Cents. 


Mj \A\y\L\^ ^ ij t 


Dolls. 


Cents. 


L> USilCia. 


Dolls. 


Cents. 


60 


I 


.90 


I 


•95 


I 


I .00 


120 


2 


1.80 


2 


1 .90 


2 


2.00 


180 


3 


2.70 


3 


2.85 


3 


3.00 


240 


4 


3.60 


4 


3.80 


4 


4.00 


300 


5 


4-5° 


5 


4-75 


5 


5-00 


360 


6 


5-40 


6 


5-70 


6 


6. CO 


420 


7 


6.30 


7 


6.65 


7 


7 .00 


480 


8 


7 . 20 


8 


7 .60 


8 


8.00 


540 


9 


8.10 


9 


8-55 


9 


9.00 


600 


10 


9.00 


10 


9-50 


10 


10.00 


660 


II 


9.90 


II 


10.45 


II 


11 .00 


720 


12 


10.80 


12 


II .40 


12 


12 .00 


780 


13 


II . 70 


13 


12-35 


13 


13.00 


840 


14 


12 .60 


14 


13-30 


14 


14.00 


900 


15 


13-50 


15 


14-25 


15 


15.00 


960 


16 


14.40 


16 


15.20 


16 


16.00 


1020 


17 


15-30 


17 


16.15 


17 


17 .00 


1080 


18 


16 . 20 


18 


17 . 10 


18 


18.00 


1 140 


19 


17.10 


19 


18.05 


19 


19.00 


1200 


20 


18.00 


20 


19.00 


20 


20.00 


1260 


21 


18.90 


21 


19-95 


21 


21 .00 


1320 


22 


19.80 


22 


20.90 


22 


22 .00 


1380 


23 


20. 70 


23 


21.85 


23 


23.00 


1440 


24 


21 .60 


24 


22.80 


24 


24.00 


1500 


25 


22.50 


25 


23-75 


25 


25 .00 


1560 


26 


23-40 


26 


24.70 


26 


26.00 


1620 


27 


24.30 


27 


25-65 


27 


27.00 


1680 


28 


25 . 20 


28 


26.60 


28 


28.00 


1740 


29 


26. 10 


29 


27-55 


29 


29.00 


1800 


30 


27 .00 


30 


28.50 


30 


30.00 


i860 


31 


27.90 


31 


29-45 


31 


31.00 


1920 


32 


28.80 


32 


30.40 


32 


32 .00 


1980 


33 


29.70 


33 


31-35 


33 


33-00 


2040 


34 


30.60 


34 


32.30 


34 


34.00 


2100 


35 


31-50 


35 


33-25 


35 


35- 00 


2160 


36 


32.40 


36 


34.20 


36 


36.00 


2220 


37 


33-30 


37 


35-15 


37 


37.00 


2280 


38 


34.20 


38 


36.10 


38 


38.00 


2340 


39 


35-10 


39 


37-05 


39 


39.00 


2400 


40 


36.00 


40 


38.00 


40 


40.00 


2460 


41 


36.90 


41 


38.95 


41 


41 .00 


2520 


42 


37.80 


42 


39-90 


42 


42 .00 


2580 


43 


38.70 . 


43 


40.85 


43 


43.00 


2640 


44 


39.60 


44 


41 .80 


44 


44.00 


2700 


45 


40.50 


45 


42.75 


45 


45.00 


2760 


46 


41.40 


46 


43 70 


46 


46.00 


2820 


47 


42.30 


47 


44.65 


47 


47.00 


2880 


48 


43.20 


48 


45.60 


48 


48.00 


2940 


49 


44.10 


49 


46.55 


49 


49.00 


3000 


50 


45.00 


50 


47.50 


50 


50.00 



MISCELLANEOUS. 529 

Calculations as to Prices of Wheat. — Continued. 







1.05. 




1.10. 




I.IS. 


Pounds. 


Bushels. 




Bushels 




Bushels. 








Dolls. 


Gents. 


MJ k4 -JL^^^^^J* 


Dolls. 


Cents. 




Dolls. 


Cents. 


60 


I 


1.05 


I 


I . 10 


I 


I-I5 


120 


2 


2 . 10 


2 


2.20 


2 


2.30 


180 


3 


3-15 


3 


3-30 


3 


3-45 


240 


4 


4 20 


4 


4-40 


4 


4.60 


300 


5 


5-25 


5 


5-50 


5 


5-75 


360 


6 


6.30 


6 


6.60 


6 


6.90 


420 


7 


7-35 


7 


7.70 


7 


8.05 


480 


8 


8.40 


8 


8.80 


8 


9. 20 


540 


9 


9-45 


9 


9.90 


9 


10.35 


600 


10 


10.50 


10 


II .00 


10 


II .50 


660 


II 


11-55 


II 


12. 10 


II 


12.65 


720 


12 


12 .60 


12 


13.20 


12 


13.80 


780 


13 


13-65 


13 


14-30 


13 


14-95 


840 


14 


14.70 


14 


15.40 


14 


16. 10 


900 


15 


15-75 


15 


16.50 


15 


17-25 


960 


16 


16.80 


16 


17 .60 


16 


18.40 


1020 


17 


17-85 


17 


18.70 


17 


19-55 


1080 


18 


18.90 


18 


19.80 


18 


20.70 


1 140 


19 


19-95 


19 


20.90 


19 


21.85 


1200 


20 


21 .00 


20 


22.00 


20 


23.00 


1260 


21 


22 .05 


21 


23.10 


21 


24-15 


1320 


22 


23.10 


22 


24.20 


22 


25-30 


1380 


23 


24-15 


23 


25-30 


23 


26.45 


1440 


24 


25-20 


24 


26.40 


24 


27 .60 


1500 


25 


26.25 


25 


27.50 


25 


28.75 


1560 


26 


27.30 


26 


28.60 


26 


29.90 


1620 


27 


28.35 


27 


29.70 


27 


31-05 


1680 


28 


29.40 


28 


30.80 


28 


32 . 20 


1740 


29 


30.45 


29 


31.90 


29 


33-35 


1800 


30 


31-50 


30 


33- 00 


30 


34-50 


i860 


3^ 


32.55 


31 


34-10 


31 


35-65 


1920 


32 


33 -60 


32 


35.20 


32 


36.80 


1980 


Z2, . 


34-65 


2>l 


36.30 


33 


37-95 


2040 


34 


35-70 


34 


37-40 


34 


39.10 


2100 


35 


36.75 


35 


38.50 


35 


40.25 


2160 


36 


37.80 


36 


39.60 


36 


41.40 


2220 


37 


38.85 


37 


40.70 


37 


42.55 


2280 


38 


39-90 


38 


41 .80 


38 


43-70 


2340 


39 


40.95 


39 


42.90 


39 


44-85 


2400 


40 


42.00 


40 


44.00 


40 


46.00 


2460 


41 


43-05 


41 


45- 10 


41 


47-15 


2520 


42 


44.10 


42 


46.20 


42 


48.30 


2580 


43 


45-15 


43 


47-30 


43 


49-45 


2640 


44 


46.20 


44 


48.40 


44 


50.60 


2700 


45 


47-25 


45 


49-50 


45 


51-75 


2760 


46 


48.30 


46 


50.60 


46 


52.90 


2820 


47 


49-35 


47 


51-70 


47 


54-05 


2880 


48 


50.40 


48 


52.80 


48 


55 -20 


2940 


49 


51-45 


49 


53-90 


49 


56.35 


3000 


50 


52.50 


50 


55-00 


50 


57-50 



530 MISCELLANEOUS. 

Calculations as to Prices of Wheat. — Continued. 







1.20. 




1.2S. 




1.30. 


PrMi n f1 c 


Bushels. 




RiiqHpI^ 




Bushels. 




X Lf Li 11 (1 b • 


Dolls. 


Cents. 


JjUOllClSa 


Dolls. 


Cents. 


Dolls. 


Cents. 


6o 


I 


I . 20 


I 


1-25 


I 


1.30 


I20 


2 


2 ,40 


2 


2.50 


2 


2 .60 


i8o 


3 


3.60 


3 


3-75 


3 


3-90 


240 


4 


4.80 


4 


5.00 


4 


5.20 


300 


5 


6.00 


5 


6.25 


5 


6.50 


360 


6 


7 . 20 


6 


7-50 


6 


7.80 


420 


7 


8.40 


7 


8.75 


7 


9. 10 


480 


8 


9.60 


8 


10.00 


8 


10.40 


540 


9 


10.80 


9 


11.25 


9 


11.70 


600 


10 


12 .00 


10 


12.50 


10 


13.00 


660 


II 


13.20 


II 


13-75 


II 


14.30 


720 


12 


14.40 


12 


15 .00 


12 


15.60 


780 


13 


15.60 


13 


16.25 


13 


16.90 


840 


14 


16.80 


14 


17-50 


14 


18.20 


900 


IS 


18.00 


15 


■ T8.75 


15 


19-50 


960 


16 


19. 20 


16 


20.00 


16 


20.80 


1020 


17 


20.40 


17 


21 . 25 


17 


22. 10 


1080 


18 


21 . 60 


18 


22.50 


18 


23.40 


II40 


19 


22 .80 


19 


23-75 


19 


24.70 


1200 


20 


24.00 


20 


25 -oo 


20 


26.00 


1260 


21 


25 . 20 


21 


26.25 


21 


27.30 


1320 


22 


26.40 


22 


27.50 


22 


28.60 


1380 


23 


27.60 


23 


28.75 


23 


29.90 


1440 


24 


28.80 


24 


30.00 


24 


31.20 


1500 


25 


30.00 


25 


31-25 


25 


32.50 


1560 


26 


31.20 


26 


32-50 


26 


33-80 


1620 


27 


32.40 


27 


33-75 


27 


35- 10 


1680 


28 


33 -60 


28 


35- 00 


28 


36.40 


1740 


29 


34.80 


29 


36-25 


29 


37-70 


1800 


30 


36.00 


30 


37-50 


30 


39.00 


i860 


31 


37.20 


31 


38-75 


31 


40.30 


1920 


32 


38.40 


32 


40.00 


32 


41 .60 


1980 


33 


39.60 


2,1 


41.25 


ZZ 


42.90 


2040 


34 


40.80 


34 


42.50 


34 


44.20 


2100 


35 


42.00 


35 


43-75 


35 


45-50 


2160 


36 


43.20 


36 


45.00 


z(^ 


46.80 


2220 


37 


44.40 


37 


46.25 


37 


48. 10 


2280 


38 


45.60 


38 


47-50 


38 


49.40 


2340 


39 


46.80 


39 


48.75 


39 


50.70 


2400 


40 


48.00 


40 


50.00 


40 


52.00 


2460 


41 


49.20 


41 


51-25 


41 


53-30 


2520 


42 


50.40 


42 


52-50 


42 


54.60 


2580 


43 


51 .60 


43 


53-75 


43 


55-90 


2640 


44 


52.80 


44 


55-00 


44 


57.20 


2700 


45 


54.00 


45 


56-25 


45 


58-50 


2760 


46 


55 -20 


46 


57-50 


46 


59.80 


2820 


47 


56.40 


47 


58.75 


47 


61 . 10 


2880 


48 


57.60 


48 


60.00 


48 


62.40 


2940 


49 


58.80 


49 


61.25 


49 


63.70 


3000 


50 


60.00 


50 


62 .50 


50 


65.00 



MISCELLANEOUS. 531 

Problems and Solutions.— Problem i — To find the circumference 
of a circle or a pulley : 

Solution. — Multiply the diameter by3.i4i6; or (approximately) as 7 is 
to 22 so is the diameter to the circumference. 
Problem 2. — To compute the diameter of a circle or a pulley : 

Solution. — Divide the circumference by 3.1416, or multiply the circum- 
ference by .3183, or (approximately) as 22 is to 7 so is the circumfer- 
ence to the diameter. 

Problem 3. — To compute the area of a circle : 

Solution. — Multiply the circumference by one quarter of the diameter, or 
multiply the square of the diameter by .7854; or multiply the square 
of the circumference by .07958 ; or multiply half the circumference 
by half the diameter ; or multiply the square of half the diameter 
by 3.1416. 

Problem 4. — To find the surface of a sphere or globe : 

Solution. — Multiply the diameter by the circumference ; or multiply the 
square of the diameter by 3.1416 ; or multiply ioui- times the square 
of the radius by 3.1416. 

Problem 5. — To compute the diameter of the pitch circle of a toothed 

wheel : 
Solutiofi. — Multiply the circular pitch in inches by the number of teeth, 

and divide by 3.1416. To get the radius of pitch circle, divide cir- 
cumference by 6.2832. 
Problem 6. — To compute the number of teeth in follower to have any given 

velocity. 
Solution. — Multiply the velocity or number of revolutions of the driver 

by its number of teeth or its diameter, and divide the product by the 

desired number of revolutions of the follower. 
Problem 7. — To compute the diameter of a follower, when the diameter of 

the driver and the number of teeth in driver and follower are given : 
Solution. — Multiply the diameter of driver by the number of teeth in the 

driven, and divide the product by the number of teeth in the driver, 

and the quotient will be the diameter of follower. 
Problem 8. — To compute the number of revolutions of a follower, when the 

number of revolutions of driver and the diameter or the number of 

teeth or driven are given : 
Solution. — Multiply the number of revolutions of driver by its number of 

teeth or its diameter, and divide the product by the number of teeth 

or the diameter of the driven. 
Problem 9. — To ascertain the number of revolutions of a driver, when the 

revolutions of driven and teeth or diameter of driver and driven are 

given ; 
Solution. — Multiply the number of teeth or the diameter of driven by its 

revolutions and divide the product by the number of teeth or the 

diameter of driver. 



532 MISCELLANEOUS. 

Problem io. — To ascertain the number of revolutions of the last wheel at 
the end of a train of spur wheels, all of which are in a line and mesh 
into one another, when the revolutions of the first wheel and the 
number of teeth or the diameter of the first and last are given : 
Solution. — Multiply the revolutions of first wheel by its number of teeth 
or its diameter and divide the product by the number of teeth or the 
diameter of the last wheel ; the result is its number of revolutions. 

Problem it. — To ascertain the number of teeth in each wheel for a train of 
spur wheels, each to have a given velocity : 
Solution. — Multiply the number of revolutions of the driving wheel by its 
number of teeth, and divide the product by the number of revolutions 
each wheel is to make, to ascertain the number of teeth required for 
each. 

Problem 12. — To compute the number of revolutions of the last wheel in a 
train of wheels and pinions, spurs or bevels, when the revolutions of 
the first or driver, and the diameter, the teeth or the circumference of 
all the drivers and pinions are given : 
Solution. — Multiply the diameter, the circumference or number of teeth of 
all the driving wheels together, and this continued product by the 
number of revolutions of the first wheel, and divide this product by 
the continued product of the diameter, the circumference or the num- 
ber of teeth of all the pinions, and the quotient will be the number of 
revolutions of the last wheel. Example : If the diameters, the cir- 
cumferences or the number of teeth of a train of wheels are 8, 8, 10, 12 
and 6. and the diameters, circumferences or number of teeth of the 
pinions are 4, 5, 5, 5 and 6, and the driver have ten revolutions, what 
will be the number of revolutions for the last pinion? Multiply all 
the drivers together and then by ten revolutions, and you have 8 by 8 
by 10 by 12 by 6 by 10 equal to 460800 ; divide this amount by the 
product of the figures for pinions 4 by 5 by 5 by 5 by 6 = 3000, 
and the quotient will be 153, or the number of revolutions of last 
wheel. This rule is equally applicable to a train of pulleys, the given 
elements being the diameter and the circumference. 

Problem 13. — To find the number of revolutions of driven pulley, the revo- 
lutions of driver anddiameter of driver and driven being given : 
Solution. — Multiply the revolutions of driver by its diameter and divide 
the product by the diameter of driven. 

Problem 14. — To compute the diameter of driven pulley for any desired 
number of revolutions, the size and velocity of driver being known : 
Solution. — Multiply the velocity of driver by its diameter and divide the 
product by the number of revolutions it is desired the driven shall 
make. 

Problem 15. — To ascertain the diameter of driving pulley : 

Solution. — Multiply the diameter of driven by the number of revolutions 
you desire it shall make, and divide the product by the number of 
revolutions of the driver. 



MISCELLANEO US. 533 

Problem i6. — -To find the velocity or number of revolutions of the last wheel 
to one of the first. 

Rule: Divide the product of the number of teeth of the wheels that act 
as driver by the product of the number of teeth in the driven. 

Example: If a wheel of 32 teeth drive a pinion of 10, on the axis of 
which there is one of 30 teeth, acting on a pinion of 8, what is the number 
of turns of the last ? 

32 30 960 

X =12. Answer. 

10 8 8 

Other problems and calculations are found throughout the text, and may 
be found by consulting the Index. 



-Cgogs «)S^§^o. =308^ 



MILLING AND ITS ACCESSORIES 



Books of Reference of Value to Millers aii<l Millwriehts. 



•^^HE following is a list of Books of Reference on Subjects connected with Milling, 
Machinery, Hydraulics, etc. : 

BAIRD. — Standard Wages Computing Tables. Folio, $5 oo 

BESANT. — A Treatise on Hydro-Mechanics. 8vo., . . . , . . . . . . . 5 oo 

BOX. — A Practical Treatise on Heat as Applied to the Useful Arts. Illustrated by 1+ Plates. i2mo., . 5 00 

BOX. — A Practical Treatise on Mill Gearing, izmc, 3 00 

BOX. — Practical Hydraulics. lamo., 2 00 

BRESSE.— Hydraulic Motors. 8vo., . 2 50 

BROWN. — Five Hundred and Seven Mechanical Movements, ismo., i 00 

BURNELL AND LAW.— Hydraulic Engineering, i 20 

CEREALIA. — A Treatise on the Different Cereals, their Character, Constituents and Analysis. Illus- 
trated, ................... 50 

COOPER. — A Treatise on the Use of Belting for the Transmission of Power. 8vo., . . . . 3 5° 

CORFIELD.— Water and Water Supply. i6mo., 50 

CRAIK. — The Practical American Millwright and Miller. Bvo., 5 00 

CULLEN. — Practical Treatise on the Construction of Horizontal and Vertical Water-Wheels. Quarto, 5 00 

DOWNING.— The Elements of Practical Hydraulics. Bvo., 2 75 

FAIRBAIRN. — The Principles of Mechanism and Machinery of Transmission. i2mo., . . . . 2 50 

FAIRBAIRN.— A Treatise on Mills and Millwork. 8vo., 10 00 

FANNING. — A Practical Treatise on Water Supply Engineering. Bvo,, 5 00 

FRANCIS. — Lowell Hydraulic Experiments on Hydraulic Motors. Quarto, . . . . . . 15 00 

GLYNN. — A Treatise on the Power of Water. i2mo., . . . . . . . . . . i 00 

GBIMSHAW Miller, Millwright and Millfurnisher. 550 Pages. Cloth. Royal 

8vo. 400 Illustrations 6 00 

HUGHES. — American Miller and Millwright's Assistant. i2mo., i 50 

JACKSON.— Hydraulic Manual. 8vo., 10 00 

JACOB. — The Designing and Construction of Storage Reservoirs. i6mo., 50 

JOHNSON. — The Practical Draughtsman's Book of Industrial Design and Machinist's and Engineer's 

Drawing Companion. With over 50 Steel Plates. Quarto, 10 00 

KIRKWOOD. — Report on the Filtration of River Waters, for the Supply of Cities, etc. Quarto, . . 15 00 

KUTTER. — The New Formula for Mean Velocity of Discharge of Rivers and Canals. 8vo., . . . 5 00 

LEFFEL.— The Construction of Mill Dams. Bvo., 2 50 

M'LEAN. — The Miller's Text Book. A Descriptive and Explanatory Account of the Various Grains 

and Processes used in Grain Mills, 60 

NEVILLE. — Hydraulic Tables, CoeflScients and Formulse for Finding the Discharge of Water from 

Orifices, Notches, Weirs, Pipes and Rivers. i2mo., .... ...... 5 00 

OVERMAN. — Mechanics for the Millwright, Engineer and Machinist. 150 Illustrations. . . . i 50 

PALLETT. — The Miller's, Millwright's-and Engineer's Guide. i2mo., 3 00 

RANKINE. — A Manual of Machinery and Millwork. i2mo., 500 

ROPER. — Use and Abuse of the Steam Boiler. By Stephen Roper. Illustrated. iBmo., tucks, gilt 

edges, 2 00 

ROPER. — Catechism of Steam Engine, 2 50 

ROPER. — Hand-Book of Land and Marine Engines, 3 50 

ROPPS. — Easy Calculator. Pocket-book form. Cloth, 1 00 

ROSE. — The Complete Practical Machinist. i2mo., . . . . . . . . . . . 2 50 

SPON. — Workshop Receipts for the Use of Manufacturers and Mechanics. T2mo., . . . . . 2 00 

URE'S DICTIONARY OF ARTS, MANUFACTURES AND MINES.— By Robert Hunt, F.R.S. 

Illustrated with nearly 2,000 engravings on wood. 1867. 4 vols., 35 00 

WEISBACH.— Hydraulics and Hydraulic Motors. With 380 Illustrations. Bvo 600 

Send Orders to HOWARD LOCKWOOD, Publisher, 

Box 3715, P. O. New York, 



Oldest, Best and Only Independent Milling 
Paper Published. 



T h: E 



itltUffS lililflsL. 



AND — 



Flour and Grain Reporter. 



Weekly, - $2.00 per Annum. | Single Copies, - Ten Cents. 



jHIS PAPER IS PUBLISHED EVERY WEDNESDAY. It is devoted to the interests 
_._ of the Flour, Milling' and Grain Trades. It presents to its readers 
illustrated descriptions of Milling Machinery and Processes, besides 
special Technical and Selected Articles, Correspondence, Trade 
News, and Regular Market Reports. The value of this paper, not only as 
a technical trade journal, but as a reference to be kept and filed, is therefore very great, 
and as a medium for trade communication and information it cannot be surpassed. 



Specimen Copies sent free on Application. <^i^ 



HOWARD LOCKWOOD, Publisher, 

No. 74 Duane Street, New York, 

p. O. Box 37 IS. 



Devoted Exclusively to the Interests of the 
Milling and Grain Trades. 



There is no art so diverse in its 
application, or so prolific in its 
results, as the art of printing. 



TiaiE-i'- 



Bad printing is an abuse of art. 
It condemns the printer and works 
injury to him who accepts it. 






AMEEICAN STATIONEE. 
AMEEICAN MAIL & EZPOET JOUENAL. 
UUSICAL COUBIEB. 



^O 



iv 




MILLEES' JOUENAL. 



EIEECTOEY OF THE PAPBS TEADE. 
WAEP AND WEFT. 



^^^ LOCKWOOD, P^°^' 



,rv 



Q^' 



,0^^ 



Wm»j f4 Mmmmm Bt^®&% 



p. O. Box 3715. 



l^T^T^T^ -^-OI^I^ 



BOOK, NEWSPAPER AND JOB 

pteam printing Establishment. 

«^ AWARDS FOR PUBLICATIONS, PRINTING AND ART. ^* 



Paris Exposition, 1878 — Diploma of Honor. 

Sydney International Exhibition, 1879-1880 
— First and Special Degree of Merit ; also 
Second Degree of Merit. 

Melbourne International Exhibition, 1880- 
1881— Four First Orders of Merit, Two Silver 
and Two Bronze Medals. 



Adelaide Exhibition, 1881 — Two Special First 
and Two First Degrees of Merit, Two Gold 
and Two Silver Medals. 

Chicago Exposition, 1881 — Highest Award. 
Cincinnati Industrial Exposition, 1881 — 
Highest Award. 

Atlanta International Cotton Exposition, 
1881— Highest Award. 



FINE CATALOGUE PRINTING A SPECIALTY. 

T I THE importance of fine work in the printing of catalogues, pamphlets, &c., cannot be too highly 
I estimated. The character of a firm is always gauged by its products, and a house that sends 
out ill-printed catalogues or other advertisements of its business secures a reputation for cheap- 
ening its work. A little — very little — more money than is charged for poor work will pay for a well 
printed catalogue, artistic in all of its details. The Lockwood Press is noted for its first-class typo- 
graphical work. It has its own steam presses and all of the appointments of a fully equipped office. 
Circulars, Catalogues or Books accurately translated and printed in English, French, German, Span- 
ish or Portuguese. Estimates furnished for good work, from a small circular to the finest catalogue 
or book. 

— o-^g LOWEST PRICES CONSISTENT WITH GOOD WORKMANSHIP. ^°— 

The undersigned will also produce, in miniature or enlarged form, by the best process yet dis- 
covered, electrotype plates of wood-cuts, price-lists, catalogues, &c., an ordinary proof-sheet being 
all that is necessary for their production. 

HOWARD LOCKWOOD, Publisher and Printer, 
No, 74: Duane Street, New York. 



PIAR -0 i9ii3 




i 



. -i^ 



